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Quantification of entanglement via uncertainties
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
A. A. Klyachko , B. Öztop , A. S. Shumovsky
Yıl :
2007
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
We show that entanglement of pure multiparty states can be quantified by means of quantum uncertainties of certain basic observables through the use of a measure that was initially proposed by Klyachko.
DOI : 10.1103/PhysRevA.75.032315
Anahtar Kelimeler : Article
Cilt: 75
Sayı: 3
ISSN: 2469-9926
Sayfa: 032315-1-032315-6
Sınıflandırma :
2
Semi-analytic theory self-similar optical propagation and mode-locking using a shape-adaptive model pulse
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
C. Jirauschek , F. O. Ilday
Konu :
Fiber laser, Parabolic pulses, Analytic theory, Locked lasers, Wave-breaking, Dynamics, Evolution, Equation, Nj
Yıl :
2014
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
A semianalytic theory for the pulse dynamics in similariton amplifiers and lasers is presented, based on a model pulse with adaptive shape. By changing a single parameter, this test function can be continuously tweaked between a pure Gaussian and a pure parabolic profile and can even represent sech-like pulses, the shape of a soliton. This approach allows us to describe the pulse evolution in the self-similar and other regimes of optical propagation. Employing the method of moments, the evolution equations for the characteristic pulse parameters are derived from the governing nonlinear Schrodinger or Ginzburg-Landau equation. Due to its greatly reduced complexity, this description allows for extensive parameter optimization, and can aid intuitive understanding of the dynamics. As an application of this approach, we model a soliton-similariton laser and validate the results against numerical simulations. This constitutes a semianalytic model of the soliton-similariton laser. Due to the versatility of the model pulse, it can also prove useful in other application areas.
DOI : 10.1103/PhysRevA.83.063809
Anahtar Kelimeler : Fiber laser, Parabolic pulses, Analytic theory, Locked lasers, Wave-breaking, Dynamics, Evolution, Equation, Nj, Article
Cilt: 83
Sayı: 6
ISSN: 1050-2947
Sayfa: 1-9
Sınıflandırma :
3
Non-Hermitian matter-wave mixing in Bose-Einstein condensates : Dissipation-induced amplification
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Sebastian Wüster , R. El-Ganainy
Yıl :
2017
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
We investigate the nonlinear scattering dynamics in interacting atomic Bose-Einstein condensates under non-Hermitian dissipative conditions. We show that, by carefully engineering a momentum-dependent atomic loss profile, one can achieve matter-wave amplification through four-wave mixing in a quasi-one-dimensional nearly-free-space setup - a process that is forbidden in the counterpart Hermitian systems due to energy mismatch. Additionally, we show that similar effects lead to rich nonlinear dynamics in higher dimensions. Finally, we propose a physical realization for selectively tailoring the momentum-dependent atomic dissipation. Our strategy is based on a two-step process: (i) exciting atoms to narrow Rydberg or metastable excited states, and (ii) introducing loss through recoil; all while leaving the bulk condensate intact due to protection by quantum interference.
DOI : 10.1103/PhysRevA.96.013605
Anahtar Kelimeler : Article
Cilt: 96
Sayı: 1
ISSN: 2469-9926
Sınıflandırma :
4
Composite quasiparticles in strongly correlated dipolar Fermi liquids
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
I. Seydi , S. H. Abedinpour , R. Asgari , Bilal Tanatar
Yıl :
2018
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Strong particle-plasmon interaction in electronic systems can lead to composite hole-plasmon excitations. We investigate the emergence of similar composite quasiparticles in ultracold dipolar Fermi liquids originating from the long-range dipole-dipole interaction. We use the G0W technique with an effective interaction obtained from the static structure factor to calculate the quasiparticle properties and single-particle spectral function. We first demonstrate that within this formalism a very good agreement with the quantum Monte Carlo results could be achieved over a wide range of coupling strengths for the renormalization constant and effective mass. The composite quasiparticle-zero sound excitations which are undamped at long wavelengths emerge at intermediate and strong couplings in the spectral function and should be detectable through the radio frequency spectroscopy of nonreactive polar molecules at high densities.
DOI : 10.1103/PhysRevA.98.063623
Anahtar Kelimeler : Article
Cilt: 98
Sayı: 6
ISSN: 2469-9926
Sayfa: 063623-1-063623-8
Sınıflandırma :
5
One-way Rayleigh-Wood anomalies and tunable narrowband transmission in photonic crystal gratings with broken structural symmetry
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
A. E. Serebryannikov , Ekmel Özbay
Konu :
Unidirectional transmission, Photonic crystal, Transmission, Rayleigh-Wood anomaly
Yıl :
2013
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
In photonic crystal (PC) gratings whose structural symmetry is broken owing to one-side corrugations, the Rayleigh-Wood anomalies can appear in a one-way manner. In the combination with the vanishing coupling to the lowest Floquet-Bloch mode at the upper band edge, these anomalies lead to the appearance of the defect-mode-like, i.e., very narrow one-way transmission, peak, which cannot appear in the corresponding slab of PC without corrugations. Such a sole peak can be transformed into a one-way transmission band with a desired width by varying angle of incidence. The nonoverlapping and thus switchable one-way (higher-order) and two-way (zero-order) transmission bands can be obtained in both the frequency and incidence-angle domains. Adjustment of PC lattice and corrugation parameters allows one to obtain two subsequent one-way bands, every being connected with a certain higher diffraction order. Conditions required for the appearance of a narrow one-way transmission band in the vicinity of a Rayleigh-Wood anomaly are well consistent with typical dispersion features of a very large class of PCs and do not need unusual performances.
DOI : 10.1103/PhysRevA.87.053804
Anahtar Kelimeler : Unidirectional transmission, Photonic crystal, Transmission, Rayleigh-Wood anomaly, Article
Cilt: 87
Sayı: 5
ISSN: 1050-2947
Sayfa: 053804-1-053804-5
Sınıflandırma :
6
Metal-insulator transition induced by random dipoles
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
M. Larcher , C. Menotti , Bilal Tanatar , P. Vignolo
Konu :
Localization length, Localization properties, Long range correlations, Random position, Random potentials, Short-range correlations, Mathematical models, Physics, Semiconductor insulator boundaries
Yıl :
2013
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
We study the localization properties of a test dipole feeling the disordered potential induced by dipolar impurities trapped at random positions in an optical lattice. This random potential is marked by correlations which are a convolution of short-range and long-range ones. We show that when short-range correlations are dominant, extended states can appear in the spectrum. Introducing long-range correlations, the extended states, if any, are wiped out and localization is restored over the whole spectrum. Moreover, long-range correlations can either increase or decrease the localization length at the center of the band, which indicates a richer behavior than previously predicted.
DOI : 10.1103/PhysRevA.88.013632
Anahtar Kelimeler : Localization length, Localization properties, Long range correlations, Random position, Random potentials, Short-range correlations, Mathematical models, Physics, Semiconductor insulator boundaries, Article
Cilt: 88
Sayı: 1
ISSN: 2469-9926
Sayfa: 013632-1-013632-8
Sınıflandırma :
7
Oral and Craniofacial manifestations of Ellis-Van Creveld syndrome
Bildiri Serisi

Bildiri Serisi
Kaynak :
DSpace Makaleler
Yayıncı :
PHYSICAL REVIEW A
Yazar(lar) :
FIGEN SEYMEN
Yıl :
2021
PHYSICAL REVIEW A
Yayıncı Web Sitesi
Kaydet
Anahtar Kelimeler : Bildiri
Sınıflandırma :
8
Ayvansaray’da Üç Yapı: Hatice Sultan Sıbyan Mektebi, Sebil ve Çeşmesi
Bildiri Serisi

Bildiri Serisi
Kaynak :
DSpace Makaleler
Yayıncı :
PHYSICAL REVIEW A
Yazar(lar) :
AKÇIL HARMANKAYA , Nesrin Çiçek
Konu :
Sanat ve Beşeri Bilimler, Sanat ve Beşeri Bilimler (AHCI), Sosyal ve Beşeri Bilimler
Yıl :
2021
PHYSICAL REVIEW A
Yayıncı Web Sitesi
Kaydet
Anahtar Kelimeler : Sanat ve Beşeri Bilimler, Sanat ve Beşeri Bilimler (AHCI), Sosyal ve Beşeri Bilimler, Bildiri
Sınıflandırma :
Mimarlık %100
9
Multiexcitons in flexible Rydberg aggregates
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
G. Abumwis , S. Wüster
Yıl :
2018
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Flexible Rydberg aggregates, assemblies of a few Rydberg atoms coherently sharing electronic excitations while undergoing directed atomic motion, show great promise as a quantum simulation platform for nuclear motion in molecules or quantum energy transport. Here we study additional features that are enabled by the presence of more than a single electronic excitation, thus considering multiexciton states. We describe cases where these can be decomposed into underlying single-exciton states and then present dynamical scenarios with atomic motion that illustrate exciton-exciton collisions, exciton routing, and strong nonadiabatic effects in simple one-dimensional settings.
DOI : 10.1103/PhysRevA.98.043606
Anahtar Kelimeler : Article
Cilt: 98
Sayı: 4
ISSN: 2469-9926
Sayfa: 043606-1-043606-6
Sınıflandırma :
10
Cat-state generation and stabilization for a nuclear spin through electric quadrupole interaction
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Ceyhun Bulutay
Yıl :
2017
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Spin cat states are superpositions of two or more coherent spin states (CSSs) that are distinctly separated over the Bloch sphere. Additionally, the nuclei with angular momenta greater than 1/2 possess a quadrupolar charge distribution. At the intersection of these two phenomena, we devise a simple scheme for generating various types of nuclear-spin cat states. The native biaxial electric quadrupole interaction that is readily available in strained solid-state systems plays a key role here. However, the fact that built-in strain cannot be switched off poses a challenge for the stabilization of target cat states once they are prepared. We remedy this by abruptly diverting via a single rotation pulse the state evolution to the neighborhood of the fixed points of the underlying classical Hamiltonian flow. Optimal process parameters are obtained as a function of electric field gradient biaxiality and nuclear-spin angular momentum. The overall procedure is seen to be robust under 5% deviations from optimal values. We show that higher-level cat states with four superposed CSS can also be formed using three rotation pulses. Finally, for open systems subject to decoherence we extract the scaling of cat-state fidelity damping with respect to the spin quantum number. This reveals rates greater than the dephasing of individual CSSs. Yet, our results affirm that these cat states can preserve their fidelities for practically useful durations under the currently attainable decoherence levels.
DOI : 10.1103/PhysRevA.96.012312
Anahtar Kelimeler : Article
Cilt: 96
Sayı: 1
ISSN: 2469-9926
Sınıflandırma :
11
On-chip quantum tomography of mechanical nanoscale oscillators with guided Rydberg atoms
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Adrian Sanz-Mora , Sebastian Wüster , Jan Michael Rost
Yıl :
2017
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Nanomechanical oscillators as well as Rydberg-atomic waveguides hosted on microfabricated chip surfaces hold promise to become pillars of future quantum technologies. In a hybrid platform with both, we show that beams of Rydberg atoms in waveguides can quantum coherently interrogate and manipulate nanomechanical elements, allowing full quantum state tomography. Central to the tomography are quantum nondemolition measurements using the Rydberg atoms as probes. Quantum coherent displacement of the oscillator is also made possible by driving the atoms with external fields while they interact with the oscillator. We numerically demonstrate the feasibility of this fully integrated on-chip control and read-out suite for quantum nanomechanics, taking into account noise and error sources.
DOI : 10.1103/PhysRevA.96.013855
Anahtar Kelimeler : Article
Cilt: 96
Sayı: 1
ISSN: 24699926
Sınıflandırma :
12
Spinal Enstrümantasyon
Kitap Bölümü

Kitap Bölümü
Kaynak :
DSpace Makaleler
Yayıncı :
PHYSICAL REVIEW A
Yazar(lar) :
Saffet TÜZGEN , Mehmet Murat HANCI
Konu :
Sağlık Bilimleri, Tıp, Klinik Tıp (MED)
Yıl :
2021
PHYSICAL REVIEW A
Yayıncı Web Sitesi
Kaydet
Anahtar Kelimeler : Sağlık Bilimleri, Tıp, Klinik Tıp (MED), Kitapta Bölüm
Sınıflandırma :
13
Vortex lattices in dipolar two-component Bose-Einstein condensates
Dergi Makalesi

Dergi Makalesi
Kaynak 1:
DSpace Makaleler
Kaynak 2:
DSpace Makaleler
Yayıncı :
PHYSICAL REVIEW A
Yazar(lar) :
N. Ghazanfari , A. Keles , M. O. Oktel
Konu :
OPTİK, Atom ve Molekül Fiziği, Elektromanyetizma, Akustik, Isı Transferi, Klasik Mekanik ve Akışkanlar Dinamiği, Optik, Temel Bilimler, Fizik, Temel Bilimler (SCI), FİZİKSEL, ATOMİK, MOLEKÜLER VE KİMYASAL
Yıl :
2014
PHYSICAL REVIEW A
Kaydet
We consider a rapidly rotating two-component Bose-Einstein condensate with short-range s-wave interactions as well as dipolar coupling. We calculate the phase diagram of vortex lattice structures as a function of the intercomponent s-wave interaction and the strength of the dipolar interaction. We find that the long-range interactions cause new vortex lattice structures to be stable and lead to a richer phase diagram. Our results reduce to the previously found lattice structures for short-range interactions and single-component dipolar gases in the corresponding limits.
Anahtar Kelimeler : OPTİK, Atom ve Molekül Fiziği, Elektromanyetizma, Akustik, Isı Transferi, Klasik Mekanik ve Akışkanlar Dinamiği, Optik, Temel Bilimler, Fizik, Temel Bilimler (SCI), FİZİKSEL, ATOMİK, MOLEKÜLER VE KİMYASAL, Makale

ISSN: 1050-2947
Sınıflandırma :
Fizik %100
14
Mott transition in a two-leg Bose-Hubbard ladder under an artificial magnetic field
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
PHYSICAL REVIEW A
Yazar(lar) :
A. Keleş , M. Ö. Oktel
Yıl :
2015
PHYSICAL REVIEW A
Yayıncı Web Sitesi Tam Metin
Kaydet
We consider the Bose-Hubbard model on a two-leg ladder under an artificial magnetic field and investigate the superfluid–to–Mott insulator transition in this setting. Recently, this system has been experimentally realized [M. Atala et al. , Nature Phys. 10 , 588 ( 2014 )], albeit in a parameter regime that is far from the Mott transition boundary. Depending on the strength of the magnetic field, the single-particle spectrum has either a single ground state or two degenerate ground states. The transition between these two phases is reflected in the many-particle properties. We first investigate these phases through the Bogoliubov approximation in the superfluid regime and calculate the transition boundary for weak interactions. For stronger interactions the system is expected to form a Mott insulator. We calculate the Mott transition boundary as a function of the magnetic field and interleg coupling with mean-field theory, strong-coupling expansion, and density matrix renormalization group (DMRG). Finally, using the DMRG, we investigate the particle-hole excitation gaps of this system at different filling factors and find peaks at simple fractions, indicating the possibility of correlated phases.
DOI : 10.1103/PhysRevA.91.013629
Anahtar Kelimeler : Article
Cilt: 91
ISSN: 2469-9926
Sayfa: 013629-1-013629-9
Sınıflandırma :
15
Wave-packet propagation in momentum space: Calculation of sharp-energy S-matrix elements
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Bilkent Üniversitesi
Yıl :
1992
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
This paper examines momentum-space methods as a means of implementing a scattering-theoretic, long-time lemma on the extraction of sharp-energy S-matrix elements from a wave-packet description of collisions. In order to concentrate on the momentum space and computational aspects, the collision system studied is that of two particles; each has the mass of a nucleon. The formulation of the problem in momentum space avoids any spreading of the packets and allows for a straightforward analysis, which proceeds as follows. First, a time discretization is introduced, so that a conditionally stable, recursive, time-evolution scheme can be employed. The momentum dependence of the full wave packet is next expressed via an expansion in locally defined interpolating polynomials (here, piecewise quadratics), as in the finite-element method. Once the time evolution has progressed sufficiently, the S-matrix element S0(q) can be extracted from the ratio of the qth momentum components of the full and free wave packets. It is essential here that the numerically propagated free wave packet be used in this ratio, since otherwise numerical errors induced in the full wave packet are not canceled, and S0(q) can become as large as 2 or more. Wave packets with central momenta q0 equal to 1, 2, and 4 fm-1 (energies ranging from about 30 to 500 MeV) have been studied, and the behavior of the wave packets and S0(q) for several time intervals, extraction times, numbers of mesh points, etc., have been explored. In general, results with errors of less than at most a few percent are easily obtainable. © 1992 The American Physical Society.
DOI : 10.1103/PhysRevA.46.2304
Anahtar Kelimeler : Article
Cilt: 46
Sayı: 5
ISSN: 10502947
Sayfa: 2304-2316
Sınıflandırma :
16
Landau levels in lattices with long - range hopping
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Hakan Atakişi , M. Özgür Oktel
Konu :
Analytic expressions, Chern numbers, Discretizations, Fractional quantum, General method, Hopping models, Landau levels, Periodic potentials, Quantum hall effect, Restoration, Wave functions
Yıl :
2013
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Landau levels (LLs) are broadened in the presence of a periodic potential, forming a barrier for accurate simulation of the fractional quantum Hall effect using cold atoms in optical lattices. Recently, it has been shown that the degeneracy of the lowest Landau level (LLL) can be restored in a tight-binding lattice if a particular form of long-range hopping is introduced. In this paper, we investigate three problems related to such quantum Hall parent Hamiltonians in lattices. First, we show that there are infinitely many long-range hopping models in which a massively degenerate manifold is formed by lattice discretizations of wave functions in the continuum LLL. We then give a general method to construct such models, which is applicable to not only the LLL but also higher LLs. We use this method to give an analytic expression for the hoppings that restores the LLL, and an integral expression for the next LL. We also consider whether the space spanned by discretized LL wave functions is as large as the space spanned by continuum wave functions, and we find the constraints on the magnetic field for this condition to be satisfied. Finally, using these constraints and the first Chern numbers, we identify the bands of the Hofstadter butterfly that correspond to continuum LLs.
DOI : 10.1103/PhysRevA.88.033612
Anahtar Kelimeler : Analytic expressions, Chern numbers, Discretizations, Fractional quantum, General method, Hopping models, Landau levels, Periodic potentials, Quantum hall effect, Restoration, Wave functions, Article
Cilt: 88
Sayı: 3
ISSN: 1050-2947
Sayfa: 033612-1-033612-10
Sınıflandırma :
17
Simulation of the breakup channel in three-particle collisions with pseudoreaction channels
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Z.C. Kuruolu
Yıl :
1991
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
A pseudochannel extension of the coupled-reaction-channel (CRC) method is investigated formally and numerically as a means of simulating the effect of the breakup channel on the rearrangement amplitudes. The equations of the pseudostate-augmented CRC method are derived within a two-Hilbert-space approach. The connection of the effective CRC transition operators with the postform transition operators of the formal scattering theory is established. Alternative formulations of the method corresponding to different ways of treating the nonorthogonality interaction are given. Convergence with respect to the number and nature of the pseudostates are investigated numerically on a solvable three-particle model. It is observed that the results obtained with six distinct sets of pseudochannels that have considerably different threshold energies converge toward the exact ones. © 1991 The American Physical Society.
DOI : 10.1103/PhysRevA.44.7307
Anahtar Kelimeler : Article
Cilt: 44
Sayı: 11
ISSN: 10502947
Sayfa: 7307-7317
Sınıflandırma :
Fizik %20
18
Rotons and Bose condensation in Rydberg-dressed Bose gases
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
I. Seydi , S. H. Abedinpour , R. E. Zillich , R. Asgari , Bilal Tanatar
Konu :
Bose gases, Bose-Einstein condensates, Cold, ultracold molecules, Rydberg atoms & molecules, Ultracold gases
Yıl :
2020
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
We investigate the ground-state properties and excitations of Rydberg-dressed bosons in both three and two dimensions, using the hypernetted-chain Euler-Lagrange approximation, which accounts for correlations and thus goes beyond the mean-field approximation. The short-range behavior of the pair distribution function signals the instability of the homogeneous system with respect to the formation of droplet crystals at strong couplings and large soft-core radius. This tendency to spatial density modulation coexists with off-diagonal long-range order. The contribution of the correlation energy to the ground-state energy is significant at large coupling strengths and intermediate values of the soft-core radius while for a larger soft-core radius the ground-state energy is dominated by the mean-field (Hartree) energy. We have also performed path integral Monte Carlo simulations at selected system parameters to verify the performance of our hypernetted-chain Euler-Lagrange results in three dimensions. In the homogeneous phase, the two approaches are in very good agreement. Moreover, Monte Carlo simulations predict a first-order quantum phase transition from a homogeneous superfluid phase to the quantum droplet phase with face-centered cubic symmetry for Rydberg-dressed bosons in three dimensions.
DOI : 10.1103/PhysRevA.101.013628
Anahtar Kelimeler : Bose gases, Bose-Einstein condensates, Cold and ultracold molecules, Rydberg atoms & molecules, Ultracold gases, Article
Cilt: 101
Sayı: 1
ISSN: 2469-9926
Sayfa: 013628-11-013628-1
19
Quantum-statistical properties of a Raman-type model
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
A. S. Shumovsky , Bilal Tanatar
Yıl :
1993
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
A model describing three boson fields with the decay of Rayleigh mode into the Stokes and vibration (phonon) modes is examined. The problem of exact eigenvalues and eigenstates is reduced to the calculation of zeros of new orthogonal polynomials defined in terms of difference and differential equations. The instability of the spectrum of eigenvalues is established. The quantum-statistical properties are investigated for various initial conditions. The possibility of using the correlation Raman spectroscopy to measure the quantum-statistical properties of the vibration mode is discussed. © 1993 The American Physical Society.
DOI : 10.1103/PhysRevA.48.4735
Anahtar Kelimeler : Article
Cilt: 48
Sayı: 6
ISSN: 1050-2947
Sayfa: 4735-4741
Sınıflandırma :
Fizik %63
20
Artificial magnetic-field quenches in synthetic dimensions
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Fırat Yılmaz , M. Özgür Oktel
Yıl :
2018
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Recent cold atom experiments have realized models where each hyperfine state at an optical lattice site can be regarded as a separate site in a synthetic dimension. In such synthetic ribbon configurations, manipulation of the transitions between the hyperfine levels provide direct control of the hopping in the synthetic dimension. This effect was used to simulate a magnetic field through the ribbon. Precise control over the hopping matrix elements in the synthetic dimension makes it possible to change this artificial magnetic field much faster than the time scales associated with atomic motion in the lattice. In this paper, we consider such a magnetic-flux quench scenario in synthetic dimensions. Sudden changes have not been considered for real magnetic fields as such changes in a conducting system would result in large induced currents. Hence we first study the difference between a time varying real magnetic field and an artificial magnetic field using a minimal six-site model. This minimal model clearly shows the connection between gauge dependence and the lack of on-site induced scalar potential terms. We then investigate the dynamics of a wave packet in an infinite two- or three-leg ladder following a flux quench and find that the gauge choice has a dramatic effect on the packet dynamics. Specifically, a wave packet splits into a number of smaller packets moving with different velocities. Both the weights and the number of packets depend on the implemented gauge. If an initial packet, prepared under zero flux in an n-leg ladder, is quenched to Hamiltonian with a vector potential parallel to the ladder, it splits into at most n smaller wave packets. The same initial wave packet splits into up to n2 packets if the vector potential is implemented to be along the rungs. Even a trivial difference in the gauge choice such as the addition of a constant to the vector potential produces observable effects. We also calculate the packet weights for arbitrary initial and final fluxes. Finally, we show that edge states in a thick ribbon are robust under the quench only when the same gap supports an edge state for the final Hamiltonian.
DOI : 10.1103/PhysRevA.97.023612
Anahtar Kelimeler : Article
Cilt: 97
Sayı: 2
ISSN: 2469-9926
Sayfa: 023612-1-023612-17
Sınıflandırma :
21
Rabi model as a quantum coherent heat engine: From quantum biology to superconducting circuits
Dergi Makalesi

Dergi Makalesi
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Ferdi Altintas , Ali U. C. Hardal , Ozgur E. Mustecaplioglu
Yıl :
2015
Physical Review A
Yayıncı Web Sitesi
Kaydet
We propose a multilevel quantum heat engine with a working medium described by a generalized Rabi model which consists of a two-level system coupled to a single-mode bosonic field. The model is constructed to be a continuum limit of a quantum biological description of light-harvesting complexes so that it can amplify quantum coherence by a mechanism which is a quantum analog of classical Huygens clocks. The engine operates in a quantum Otto cycle where the working medium is coupled to classical heat baths in the isochoric processes of the four-stroke cycle, while either the coupling strength or the resonance frequency is changed in the adiabatic stages. We found that such an engine can produce work with an efficiency close to the Carnot bound when it operates at low temperatures and in the ultrastrong-coupling regime. The interplay of the effects of quantum coherence and quantum correlations on the engine performance is discussed in terms of second-order coherence, quantum mutual information, and the logarithmic negativity of entanglement. We point out that the proposed quantum Otto engine can be implemented experimentally with modern circuit quantum electrodynamic systems where flux qubits can be coupled ultrastrongly to superconducting transmission-line resonators.
Cilt: 91
Sayı: 2
ISSN: 1050-2947
Sınıflandırma :
22
Oral Kematerapötik ilaçlara bağlı geç tip hipersensitivite reaksiyonlarında on altı günlük desensitizasyon protokolü
Bildiri Serisi

Bildiri Serisi
Kaynak :
DSpace Makaleler
Yayıncı :
PHYSICAL REVIEW A
Yazar(lar) :
SUNA BUYUKORTURK , M OLGAC , R COSKUN , SEMRA DEMİR , Aslı GELINCIK , BAHATTIN COLAKOĞLU , D. UNAL
Konu :
Klinik Tıp (MED), Tıp, Sağlık Bilimleri
Yıl :
2021
PHYSICAL REVIEW A
Yayıncı Web Sitesi
Kaydet
Anahtar Kelimeler : Klinik Tıp (MED), Tıp, Sağlık Bilimleri, Bildiri
Sınıflandırma :
23
Phase diagram and dynamics of Rydberg-dressed fermions in two dimensions
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
R. Khasseh , S. H. Abedinpour , Bilal Tanatar
Konu :
Approximation algorithms, Fermi liquids, Ground state, Collective modes, Density oscillations, Ground state properties, Homogeneous system, Local-field factors, Ordered phasis, Random phase approximations, Spectral weight, Hartree approximation
Yıl :
2017
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
We investigate the ground-state properties and the collective modes of a two-dimensional two-component Rydberg-dressed Fermi liquid in the dipole-blockade regime. We find instability of the homogeneous system toward phase-separated and density ordered phases, using the Hartree-Fock and random-phase approximations, respectively. The spectral weight of collective density oscillations in the homogenous phase also signals the emergence of density-wave instability. We examine the effect of exchange hole on the density-wave instability and on the collective-mode dispersion using the Hubbard local-field factor.
DOI : 10.1103/PhysRevA.96.053611
Anahtar Kelimeler : Approximation algorithms, Fermi liquids, Ground state, Collective modes, Density oscillations, Ground state properties, Homogeneous system, Local-field factors, Ordered phasis, Random phase approximations, Spectral weight, Hartree approximation, Article
Cilt: 96
Sayı: 5
ISSN: 2469-9926
Sayfa: 053611-1-053611-7
Sınıflandırma :
24
Evolution of the Hofstadter butterfly in a tunable optical lattice
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
F. Yllmaz , F. N. Ünal , M. O. Oktel
Konu :
Crystal lattices, Geometry, Honeycomb structures, Magnetic fields, Optical materials, Topology, Applied magnetic fields, Checkerboard lattices, Honeycomb lattices, Real space structure, Self-similar fractals, Topological equivalence, Topological properties, Zero magnetic fields, Optical lattices
Yıl :
2015
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Recent advances in realizing artificial gauge fields on optical lattices promise experimental detection of topologically nontrivial energy spectra. Self-similar fractal energy structures generally known as Hofstadter butterflies depend sensitively on the geometry of the underlying lattice, as well as the applied magnetic field. The recent demonstration of an adjustable lattice geometry [L. Tarruell, D. Greif, T. Uehlinger, G. Jotzu, and T. Esslinger, Nature (London) 483, 302 (2012)NATUAS0028-083610.1038/nature10871] presents a unique opportunity to study this dependence. In this paper, we calculate the Hofstadter butterflies that can be obtained in such an adjustable lattice and find three qualitatively different regimes. We show that the existence of Dirac points at zero magnetic field does not imply the topological equivalence of spectra at finite field. As the real-space structure evolves from the checkerboard lattice to the honeycomb lattice, two square-lattice Hofstadter butterflies merge to form a honeycomb lattice butterfly. This merging is topologically nontrivial, as it is accomplished by sequential closings of gaps. Ensuing Chern number transfer between the bands can be probed with the adjustable lattice experiments. We also calculate the Chern numbers of the gaps for qualitatively different spectra and discuss the evolution of topological properties with underlying lattice geometry.
DOI : 10.1103/PhysRevA.91.063628
Anahtar Kelimeler : Crystal lattices, Geometry, Honeycomb structures, Magnetic fields, Optical materials, Topology, Applied magnetic fields, Checkerboard lattices, Honeycomb lattices, Real space structure, Self-similar fractals, Topological equivalence, Topological properties, Zero magnetic fields, Optical lattices, Article
Cilt: 91
Sayı: 6
ISSN: 2469-9926
Sayfa: 063628-1-063628-10
Sınıflandırma :
25
Hofstadter butterfly evolution in the space of two-dimensional bravais lattices
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
F. Yllmaz , M. Ö. Oktel
Konu :
Crystal lattices, Geometry, Magnetic fields, Optical materials, Spectroscopy, Lattice geometry, One-dimensional chains, Periodic potentials, Rectangular lattices, Self-similar spectra, Tight binding model, Two-dimensional lattices, Wannier functions, Optical lattices
Yıl :
2017
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
The self-similar energy spectrum of a particle in a periodic potential under a magnetic field, known as the Hofstadter butterfly, is determined by the lattice geometry as well as the external field. Recent realizations of artificial gauge fields and adjustable optical lattices in cold-atom experiments necessitate the consideration of these self-similar spectra for the most general two-dimensional lattice. In a previous work [F. Yllmaz, Phys. Rev. A 91, 063628 (2015)PLRAAN1050-294710.1103/PhysRevA.91.063628], we investigated the evolution of the spectrum for an experimentally realized lattice which was tuned by changing the unit-cell structure but keeping the square Bravais lattice fixed. We now consider all possible Bravais lattices in two dimensions and investigate the structure of the Hofstadter butterfly as the lattice is deformed between lattices with different point-symmetry groups. We model the optical lattice with a sinusoidal real-space potential and obtain the tight-binding model for any lattice geometry by calculating the Wannier functions. We introduce the magnetic field via Peierls substitution and numerically calculate the energy spectrum. The transition between the two most symmetric lattices, i.e., the triangular and the square lattices, displays the importance of bipartite symmetry featuring deformation as well as closing of some of the major energy gaps. The transitions from the square to rectangular lattice and from the triangular to centered rectangular lattices are analyzed in terms of coupling of one-dimensional chains. We calculate the Chern numbers of the major gaps and Chern number transfer between bands during the transitions. We use gap Chern numbers to identify distinct topological regions in the space of Bravais lattices.
DOI : 10.1103/PhysRevA.95.063628
Anahtar Kelimeler : Crystal lattices, Geometry, Magnetic fields, Optical materials, Spectroscopy, Lattice geometry, One-dimensional chains, Periodic potentials, Rectangular lattices, Self-similar spectra, Tight binding model, Two-dimensional lattices, Wannier functions, Optical lattices, Article
Cilt: 95
Sayı: 6
ISSN: 2469-9926
Sayfa: 063628-1-063628-11
Sınıflandırma :
26
Asymmetric Fabry-Perot-type transmission in photonic-crystal gratings with one-sided corrugations at a two-way coupling
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
A. E. Serebryannikov , K. B. Alici , T. Magath , A. O. Cakmak , Ekmel Özbay
Konu :
Asymmetric transmissions, Corrugation parameters, Floquet-Bloch mode, Group index, Isotropic materials, Normal incidence, Spatial inversion symmetry, Transmission mechanisms, Two-dimensional photonic crystals, Two-way coupling, Zero order, Diffraction gratings, Microcomputers, Refractive index, Fabry-perot interferometers
Yıl :
2012
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
Strongly asymmetric Fabry-Perot-type transmission arising at the two-way coupling has been studied in the case of normal incidence for slabs of two-dimensional photonic crystals (PCs) with one-sided corrugations that are made of linear isotropic materials. Comparing to the scenario of unidirectional transmission known for the structures with broken spatial inversion symmetry that requires zero order being uncoupled, in the studied mechanism zero order is either the sole order or one of the orders that may be coupled to a Floquet-Bloch mode. Contrary to the earlier studies of asymmetric transmission at the coupled zero order, structures with nondeep corrugations are considered, which allow one to combine Fabry-Perot-type total-transmission maxima with diffractions in a desired way. At a proper choice of PC lattice and corrugation parameters, higher orders can dominate in Fabry-Perot-type transmission at the noncorrugated-side illumination and also at the total-transmission maxima, whereas only zero order contributes to the transmission at the corrugated-side illumination. As a result, strong asymmetry can be obtained without uncoupling of zero order but it invokes the unidirectional contribution of higher orders. The presented results show that the entire structure can be approximately decomposed into the two independent, regular and grating (nonregular), parts whose contributions to the transmission are additive. Multiple asymmetric transmission maxima can coexist with a rather high equivalent group index of refraction. Possible applications of the studied transmission mechanism are discussed.
DOI : 10.1103/PhysRevA.86.053835
Anahtar Kelimeler : Asymmetric transmissions, Corrugation parameters, Floquet-Bloch mode, Group index, Isotropic materials, Normal incidence, Spatial inversion symmetry, Transmission mechanisms, Two-dimensional photonic crystals, Two-way coupling, Zero order, Diffraction gratings, Microcomputers, Refractive index, Fabry-perot interferometers, Article
Cilt: 86
Sayı: 5
ISSN: 1050-2947
Sayfa: 053835-1-053835-9
Sınıflandırma :
27
Heat transfer through dipolar coupling: Sympathetic cooling without contact
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
B. Renklioglu , Bilal Tanatar , M. Ö. Oktel
Konu :
Approximation algorithms, Cooling, Electron gas, Energy transfer, Fermions, Molecules, Correlation effect, Dipolar couplings, Dipole dipole interactions, Effective interactions, Hypernetted chain approximations, Random phase approximations, Sympathetic cooling, Temperature differences, Heat transfer
Yıl :
2016
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
We consider two parallel layers of dipolar ultracold Fermi gases at different temperatures and calculate the heat transfer between them. The effective interactions describing screening and correlation effects between the dipoles in a single layer are modeled within the Euler-Lagrange Fermi-hypernetted-chain approximation. The random-phase approximation is used for the interactions across the layers. We investigate the amount of transferred power between the layers as a function of the temperature difference. Energy transfer arises due to the long-range dipole-dipole interactions. A simple thermal model is established to investigate the feasibility of using the contactless sympathetic cooling of the ultracold polar atoms and molecules. Our calculations indicate that dipolar heat transfer is effective for typical polar molecule experiments and may be utilized as a cooling process.
DOI : 10.1103/PhysRevA.93.023620
Anahtar Kelimeler : Approximation algorithms, Cooling, Electron gas, Energy transfer, Fermions, Molecules, Correlation effect, Dipolar couplings, Dipole dipole interactions, Effective interactions, Hypernetted chain approximations, Random phase approximations, Sympathetic cooling, Temperature differences, Heat transfer, Article
Cilt: 93
Sayı: 2
ISSN: 2469-9926
Sınıflandırma :
28
Dissipative dynamics of quantum correlations in the strong-coupling regime
Dergi Makalesi

Dergi Makalesi
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
Ferdi Altintas , Resul Eryigit
Yıl :
2013
Physical Review A
Yayıncı Web Sitesi
Kaydet
The dynamics of entanglement and quantum discord between two identical qubits strongly interacting with a common single mode leaky cavity field have been investigated beyond the rotating wave approximation (RWA) by using a recently derived Lindblad type quantum optical master equation [F. Beaudoin, J. M. Gambetta, and A. Blais, Phys. Rev. A 84, 043832 (2011)] that can describe the losses of the cavity field in a strong atom-field coupling regime. Contrary to previous investigations of the same model in the dissipative regime by using the standard Lindblad quantum optical master equation in a strong-coupling regime, the atom-field steady states are found to be cavity decay rate independent and have a very simple structure determined solely by the overlap of initial atomic state with the subradiant state which is valid for all coupling regimes. Non-RWA dynamics are found to have remarkable effects on the steady state quantum discord and entanglement that cannot be achieved under RWA conditions, for instance, they can induce steady state entanglement even for the initial states that have no overlap with the subradiant state. Moreover, the non-RWA dynamics are found to reverse the initial state dependence of steady state entanglement and quantum discord contrary to the RWA case. DOI: 10.1103/PhysRevA.87.022124
Cilt: 87
Sayı: 2
ISSN: 1050-2947
Sınıflandırma :
29
Nonequilibrium fractional Hall response after a topological quench
Dergi Makalesi

Dergi Makalesi Open Access
Kaynak :
DSpace Makaleler
Yayıncı :
Physical Review A
Yazar(lar) :
F. N. Ünal , E. J. Mueller , M. O. Oktel
Konu :
Mathematical models, Physics, Finite size effect, Hall conductivity, Harmonic confinement, Integer values, Linear response, nocv1, Non equilibrium, Single Dirac cones, Universal behaviors, Topology
Yıl :
2016
Physical Review A
Yayıncı Web Sitesi Tam Metin
Kaydet
We theoretically study the Hall response of a lattice system following a quench where the topology of a filled band is suddenly changed. In the limit where the physics is dominated by a single Dirac cone, we find that the change in the Hall conductivity is two-thirds of the quantum of conductivity. We explore this universal behavior in the Haldane model and discuss cold-atom experiments for its observation. Beyond the linear response, the Hall effect crosses over from fractional to integer values. We investigate finite-size effects and the role of harmonic confinement.
DOI : 10.1103/PhysRevA.94.053604
Anahtar Kelimeler : Mathematical models, Physics, Finite size effect, Hall conductivity, Harmonic confinement, Integer values, Linear response, nocv1, Non equilibrium, Single Dirac cones, Universal behaviors, Topology, Article
Cilt: 94
Sayı: 5
ISSN: 2469-9926
Sınıflandırma :

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