Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1107.3694 · Laser Physics

Mesoscopic disorder in double-well optical lattices

Vyacheslav I. Yukalov, Elizaveta P. Yukalova

Published Jun 23, 2011• 12 citations
arXivHTMLPDF

Abstract

Double-well optical lattices are considered, each cite of which is formed by a double-well potential. The lattice is assumed to be in an insulating state and order and disorder are defined with respect to the displacement of atoms inside the double-well potential. It is shown that in such lattices, in addition to purely ordered and disordered states, there, can exist an intermediate mixed state, where, inside a generally ordered lattice, there appear disordered regions of mesoscopic size.

DOI
10.1134/s1054660x11150321

Related papers

Double-well optical lattices with atomic vibrations and mesoscopic disorder

Vyacheslav I. Yukalov, Elizaveta P. Yukalova

Double-well optical lattice in an insulating state is considered. The influence of atomic vibrations and mesoscopic disorder on the properties of the lattice are studied. Vibrations lead to the renormalization of atomic interactions. The occurrence of mesoscopic disorder results in the appearance of first-order phase transitions between the states with different levels of atomic imbalance. The existence of a nonuniform external potential, such as trapping potential, essentially changes the lattice properties, suppressing the disorder fraction and rising the transition temperature.

arXiv:1205.4529•Laser Physics•May 11, 2012•8 citations

Double-Well Optical Lattices with Atomic Vibrations and Mesoscopic Disorder

Vyacheslav I. Yukalov, Elizaveta P. Yukalova

Double-well optical lattice in an insulating state is considered. The influence of atomic vibrations and mesoscopic disorder on the properties of the lattice are studied. Vibrations lead to the renormalization of atomic interactions. The occurrence of mesoscopic disorder results in the appearance of first-order phase transitions between the states with different levels of atomic imbalance. The existence of a nonuniform external potential, such as trapping potential, essentially changes the lattice properties, suppressing the disorder fraction and rising the transition temperature.

•Aug 17, 2016•6 citations

Cold atoms in double-well optical lattices

Vyacheslav I. Yukalov, Elizaveta P. Yukalova

Cold atoms, loaded into an optical lattice with double-well sites, are considered. Pseudospin representation for an effective Hamiltonian is derived. The system in equilibrium displays two phases, ordered and disordered. The second-order phase transition between the phases can be driven either by temperature or by changing the system parameters. Collective pseudospin excitations have a gap disappearing at the phase-transition point. Dynamics of atoms is studied when they are loaded into the lattice in an initially nonequilibrium state. It is shown that the temporal evolution of atoms, contrary to their equilibrium thermodynamics, cannot be described in the mean-field approximation, since it results in a structurally unstable dynamical system, but a more accurate description is necessary taking into account attenuation effects.

arXiv:0812.3767•Physical Review A•Dec 17, 2008•26 citations

Mesoscopic Quantum Coherence in an Optical Lattice

D. L. Haycock, Paul M. Alsing, Ivan Deutsch +2 more

We observe the quantum coherent dynamics of atomic spinor wave packets in the double-well potentials of a far-off-resonance optical lattice. With appropriate initial conditions the system Rabi oscillates between the left and right localized states of the ground doublet, and at certain times the wave packet corresponds to a coherent superposition of these mesoscopically distinct quantum states. The atom/optical double-well potential is a flexible and powerful system for further study of quantum coherence, quantum control, and the quantum/classical transition.

arXiv:quant-ph/0005091•Physical Review Letters•Oct 16, 2000•66 citations

Bose-Einstein condensation and/or modulation of "displacements" in the two-state Bose-Hubbard model

Stasyuk, O. V. Velychko

Instabilities resulting in Bose-Einstein condensation and/or modulation of "displacements" in a system of quantum particles described by a two-state Bose-Hubbard model (with an allowance for the interaction between particle displacements on different lattice sites) are investigated.A possibility of modulation, which doubles the lattice constant, as well as the uniform displacement of particles from equilibrium positions are studied.Conditions for realization of the mentioned instabilities and phase transitions into the SF phase and into the "ordered" phase with frozen displacements are analyzed.The behaviour of order parameters is investigated and phase diagrams of the system are calculated both analytically (ground state) and numerically (at non-zero temperatures).It is revealed that the SF phase can appear as an intermediate one between the normal and "ordered" phases, while a supersolid phase is thermodynamically unstable and does not appear.The relation of the obtained results to the lattices with the double-well local potentials is discussed.

arXiv:1806.09927•Condensed Matter Physics•Jun 1, 2018•0 citations

Trapped Ultracold Fermions in Double-Well Optical Lattices

Atsushi Yamamoto, Makoto Yamashita, Norio Kawakami

We study the ground state properties of ultracold fermions trapped in a one-dimensional double-well optical lattice by using the density-matrix renormalization group method. The system is described by an extended Hubbard model with alternating hopping integrals and an external harmonic confining potential. We clarify the characteristic features of the metal–insulator phase transition originating from the double-well structure of the lattices. Several different types of insulating regions coexist when the number of atoms at each site is an integer or a half integer. We found that each insulating phase except for a band insulator exhibits rather large local density fluctuations, reflecting the strong dimerization of atoms within the unit cells of double-well lattices. The phase characteristics are elucidated in detail by investigating the profiles of the local density of atoms, the local density (spin) fluctuations, the double-occupancy probability and the spatially extended sp in correlations.

Journal of the Physical Society of Japan•Dec 10, 2009•1 citation
Double-well optical lattices are considered, each cite of which is formed by a double-well potential. The lattice is assumed to be in an insulating state and order and disorder are defined with respect to the displacement of atoms inside the double-well potential. It is shown that in such lattices, in addition to purely ordered and disordered states, there, can exist an intermediate mixed state, where, inside a generally ordered lattice, there appear disordered regions of mesoscopic size.
Double-well optical lattice in an insulating state is considered. The influence of atomic vibrations and mesoscopic disorder on the properties of the lattice are studied. Vibrations lead to the renormalization of atomic interactions. The occurrence of mesoscopic disorder results in the appearance of first-order phase transitions between the states with different levels of atomic imbalance. The existence of a nonuniform external potential, such as trapping potential, essentially changes the lattice properties, suppressing the disorder fraction and rising the transition temperature.
Double-well optical lattice in an insulating state is considered. The influence of atomic vibrations and mesoscopic disorder on the properties of the lattice are studied. Vibrations lead to the renormalization of atomic interactions. The occurrence of mesoscopic disorder results in the appearance of first-order phase transitions between the states with different levels of atomic imbalance. The existence of a nonuniform external potential, such as trapping potential, essentially changes the lattice properties, suppressing the disorder fraction and rising the transition temperature.
Cold atoms, loaded into an optical lattice with double-well sites, are considered. Pseudospin representation for an effective Hamiltonian is derived. The system in equilibrium displays two phases, ordered and disordered. The second-order phase transition between the phases can be driven either by temperature or by changing the system parameters. Collective pseudospin excitations have a gap disappearing at the phase-transition point. Dynamics of atoms is studied when they are loaded into the lattice in an initially nonequilibrium state. It is shown that the temporal evolution of atoms, contrary to their equilibrium thermodynamics, cannot be described in the mean-field approximation, since it results in a structurally unstable dynamical system, but a more accurate description is necessary taking into account attenuation effects.
We observe the quantum coherent dynamics of atomic spinor wave packets in the double-well potentials of a far-off-resonance optical lattice. With appropriate initial conditions the system Rabi oscillates between the left and right localized states of the ground doublet, and at certain times the wave packet corresponds to a coherent superposition of these mesoscopically distinct quantum states. The atom/optical double-well potential is a flexible and powerful system for further study of quantum coherence, quantum control, and the quantum/classical transition.
Instabilities resulting in Bose-Einstein condensation and/or modulation of "displacements" in a system of quantum particles described by a two-state Bose-Hubbard model (with an allowance for the interaction between particle displacements on different lattice sites) are investigated.A possibility of modulation, which doubles the lattice constant, as well as the uniform displacement of particles from equilibrium positions are studied.Conditions for realization of the mentioned instabilities and phase transitions into the SF phase and into the "ordered" phase with frozen displacements are analyzed.The behaviour of order parameters is investigated and phase diagrams of the system are calculated both analytically (ground state) and numerically (at non-zero temperatures).It is revealed that the SF phase can appear as an intermediate one between the normal and "ordered" phases, while a supersolid phase is thermodynamically unstable and does not appear.The relation of the obtained results to the lattices with the double-well local potentials is discussed.
We study the ground state properties of ultracold fermions trapped in a one-dimensional double-well optical lattice by using the density-matrix renormalization group method. The system is described by an extended Hubbard model with alternating hopping integrals and an external harmonic confining potential. We clarify the characteristic features of the metal–insulator phase transition originating from the double-well structure of the lattices. Several different types of insulating regions coexist when the number of atoms at each site is an integer or a half integer. We found that each insulating phase except for a band insulator exhibits rather large local density fluctuations, reflecting the strong dimerization of atoms within the unit cells of double-well lattices. The phase characteristics are elucidated in detail by investigating the profiles of the local density of atoms, the local density (spin) fluctuations, the double-occupancy probability and the spatially extended sp in correlations.