Untitled

Bukov, V. N.

doi:10.1023/a:1023234229501

Cited by 37 publications

(53 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…and the total Hamiltonian of the system is given as σ H σ (t). Assuming that the system experiences a timeevolution away from the adiabatic limit with the application of high frequency laser Ω ω c , the magnon motion is described by the effective Floquet Hamiltonian [31] We remark that though the magnetic field is accompanied by the laser electric field, it does not couple to the orbital motion of magnons, i.e., the linear momentum of magnons but enters the magnon energy directly through the Zeeman coupling without affecting orbital motion. After time-averaging, the effect of the timevarying magnetic field on the magnon energy can be captured by renormalizing the energy gap of magnons, and up and down magnons are still degenerate due to the easy-axis spin anisotropy and the resultant magnon energy gap [60].…”

Section: Magnon Motion In Lasermentioning

confidence: 95%

“…Thus we study the effects of the coupling of an ac electric field of laser to orbital motion of magnons on the magnon bands, looking for possible laser-induced topological phases of magnons. In this paper, our consideration is restricted to the magnon dynamics in the high frequency region Ω ω c , where the Floquet Hamiltonian [31] of Eq. (3) can be analyzed through the high-frequency expansion.…”

Section: Magnon Motion In Lasermentioning

confidence: 99%

“…where T is the time-ordering, we can calculate it for the high frequency regime Ω ω c in the perturbation way using the high frequency expansion [19,31],…”

Section: Appendix: Floquet Formalismmentioning

confidence: 99%

“…We treat the effect of the laser as a time-periodic electric field, which is incorporated into the Hamiltonian as the time-periodic AC potential. This system can be analyzed by the Floquet theory and in the high frequency regime, we can obtain the effective Floquet Hamiltonian [19,31] by the high frequency expansion. We find that the linearly polarized laser with nonzero time-averaged field induces helical magnon edge states, while the circularly polarized laser induces a pair of chiral magnon edge states (Fig.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Laser control of magnonic topological phases in antiferromagnets

2019

View full text Add to dashboard Cite

We study the laser control of magnon topological phases induced by the Aharonov-Casher effect in insulating antiferromagnets (AFs). Since the laser electric field can be considered as a timeperiodic perturbation, we apply the Floquet theory and perform the inverse frequency expansion by focusing on the high frequency region. Using the obtained effective Floquet Hamiltonian, we study nonequilibrium magnon dynamics away from the adiabatic limit and its effect on topological phenomena. We show that a linearly polarized laser can generate helical edge magnon states and induce the magnonic spin Nernst effect, whereas a circularly polarized laser can generate chiral edge magnon states and induce the magnonic thermal Hall effect. In particular, in the latter, we find that the direction of the magnon chiral edge modes and the resulting thermal Hall effect can be controlled by the chirality of the circularly polarized laser through the change from the left-circular to the right-circular polarization. Our results thus provide a handle to control and design magnon topological properties in the insulating AF. arXiv:1907.07636v1 [cond-mat.mes-hall]

show abstract

Section: Magnon Motion In Lasermentioning

confidence: 95%

Section: Magnon Motion In Lasermentioning

confidence: 99%

“…where T is the time-ordering, we can calculate it for the high frequency regime Ω ω c in the perturbation way using the high frequency expansion [19,31],…”

Section: Appendix: Floquet Formalismmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Laser control of magnonic topological phases in antiferromagnets

2019

View full text Add to dashboard Cite

show abstract

“…We significantly expand the relevance of quench induced dynamical quasicondensation by examining its interplay with a simultaneously applied strong periodic driving. The effect of time periodic external fields can be captured by Floquet theory [68][69][70] and has been successfully used to predict and explain wide ranging phenomena in condensed matter and cold-atoms systems. Seminal examples include induced topological effects for cold-atoms via optical lattice modulation [71,72] or exposure to circularly polarised light [73,74] in solids, dynamical localization induced Mott transitions [75,76], effective repulsive to attractive interaction conversion by bandflipping [77], and the renormalization of the super-exchange interaction [33,78,79].…”

Section: Introductionmentioning

confidence: 99%

Controllable finite-momenta dynamical quasicondensation in the periodically driven one-dimensional Fermi-Hubbard model

Cook

Clark

2020

Phys. Rev. A

View full text Add to dashboard Cite

In the strongly interacting limit of the Hubbard model localized double-occupancies form effective hardcore bosonic excitations, called a doublons, which are long-lived due to energy conservation. Using timedependent density-matrix renormalisation group we investigate numerically the dynamics of doublons arising from the sudden expansion of a spatially confined band-insulating state in one spatial dimension. By analysing the occupation scaling of the natural orbitals within the many-body state, we show that doublons dynamically quasicondense at the band edges, consistent with the spontaneous emergence of an η-quasicondensate. Building on this, we study the effect of periodically driving the system during the expansion. Floquet analysis reveals that doublon-hopping and doublon-repulsion are strongly renormalised by the drive, breaking the η−SU(2) symmetry of the Hubbard model. Numerical simulation of the driven expansion dynamics demonstrate that the momentum in which doublons quasicondense can be controlled by the driving amplitude. These results point to new pathways for engineering non-equilibrium condensates in fermionic cold-atom experiments and are potentially relevant to driven solid-state systems.

show abstract

Calculating Floquet states of large quantum systems: A parallelization strategy and its cluster implementation

Laptyeva

Kozinov

Meyerov

et al. 2016

Computer Physics Communications

View full text Add to dashboard Cite

We present a numerical approach to calculate non-equilibrium eigenstates of a periodically time-modulated quantum system. The approach is based on the use of a chain of single-step time-independent propagating operators. Each operator is time-specific and constructed by combining the Magnus expansion of the time-dependent system Hamiltonian with the Chebyshev expansion of an operator exponent. A construction of a unitary matrix of the Floquet operator, which evolves a system state over the full modulation period, is performed by propagating the identity matrix over the period. The independence of the evolutions of basis vectors makes the propagation stage suitable for implementation on a parallel cluster. Once the propagation stage is completed, a routine diagonalization of the Floquet matrix is performed. Finally, an additional propagation round, now with the eigenvectors as the initial states, allows to resolve the time-dependence of the Floquet states and calculate their characteristics. We demonstrate the accuracy and scalability of the algorithm by applying it to calculate the Floquet states of two quantum models, namely (i) a synthesized random-matrix Hamiltonian and (ii) a many-body Bose-Hubbard dimer, both of the size up to 10 4 states.the Hamiltonian H(t) but instead of the unitary Floquet operator

show abstract

Untitled

Cited by 37 publications

References 9 publications

Laser control of magnonic topological phases in antiferromagnets

Laser control of magnonic topological phases in antiferromagnets

Controllable finite-momenta dynamical quasicondensation in the periodically driven one-dimensional Fermi-Hubbard model

Calculating Floquet states of large quantum systems: A parallelization strategy and its cluster implementation

Contact Info

Product

Resources

About