We analyze the time evolution of a magnetic excitation in a spin- $\frac{1}{2}$ antiferromagnetic Heisenberg chain after a quantum quench. By a proper modulation of the magnetic exchange coupling, we prepare a static soliton of total spin $\frac{1}{2}$ as an initial spin state. Using bosonization and a numerical time-dependent density matrix renormalization group algorithm, we show that the initial excitation evolves to a state composed of two counterpropagating chiral states, which interfere to yield $\ensuremath{\langle}{S}^{z}\ensuremath{\rangle}=\frac{1}{4}$ for each mode. We find that these dynamically generated states remain considerably stable as time evolution is carried out. We propose spin-Peierls materials and ultracold-atom systems as suitable experimental scenarios in which to conduct and observe this mechanism.We analyze the time evolution of a magnetic excitation in a spin-$\frac{1}{2}$ antiferromagnetic Heisenberg chain after a quantum quench. By a proper modulation of the magnetic exchange coupling, we prepare a static soliton of total spin $\frac{1}{2}$ as an initial spin state. Using bosonization and a numerical time-dependent density matrix renormalization group algorithm, we show that the initial excitation evolves to a state composed of two counterpropagating chiral states, which interfere to yield $\ensuremath{\langle}{S}^{z}\ensuremath{\rangle}=\frac{1}{4}$ for each mode. We find that these dynamically generated states remain considerably stable as time evolution is carried out. We propose spin-Peierls materials and ultracold-atom systems as suitable experimental scenarios in which to conduct and observe this mechanism.

arXiv:1309.2013Physical Review BNov 13, 20131 citation

Soliton collisions in Bose-Einstein condensates with current-dependent interactions

Qian Jia, Haibo Qiu, Antonio Muñoz Mateo

We study general collisions between chiral solitons in Bose-Einstein condensates subject to combined attractive and current-dependent interatomic interactions. A simple analysis based on the linear superposition of the solitons allows us to determine the relevant time and space scales of the dynamics, which is illustrated by extensive numerical simulations. By varying the differential amplitude, the relative phase, the average velocity, and the relative velocity of the solitons, we characterize the different dynamical regimes that give rise to oscillatory and interference phenomena. Apart from the known inelastic character of the collisions, we show that the chiral dynamics involves an amplitude reduction with respect to the case of regular solitons. To compare these results with feasible ultracold-gas experiments, the influence of harmonic confinement is analyzed in both the emergence and the interaction of chiral solitons.We study general collisions between chiral solitons in Bose-Einstein condensates subject to combined attractive and current-dependent interatomic interactions. A simple analysis based on the linear superposition of the solitons allows us to determine the relevant time and space scales of the dynamics, which is illustrated by extensive numerical simulations. By varying the differential amplitude, the relative phase, the average velocity, and the relative velocity of the solitons, we characterize the different dynamical regimes that give rise to oscillatory and interference phenomena. Apart from the known inelastic character of the collisions, we show that the chiral dynamics involves an amplitude reduction with respect to the case of regular solitons. To compare these results with feasible ultracold-gas experiments, the influence of harmonic confinement is analyzed in both the emergence and the interaction of chiral solitons.

arXiv:2208.09972Physical Review ADec 19, 20229 citations

QUANTUM ANTIFERROMAGNETS IN TWO DIMENSIONS

Subir Sachdev A

Feb 1, 19956 citations

TWO-DIMENSIONAL QUANTUM ANTIFERROMAGNETS

Grégoire Misguich, C. Lhuillier

WORLD SCIENTIFIC eBooksJun 24, 202026 citations

Nonlinear chiral quantum dynamics of Bose-Einstein condensates under a density-dependent gauge field

Chun-Long Ma, Ai‐Xia Zhang, Xin Qiao +2 more

Abstract We investigate chiral quantum dynamics of a Bose-Einstein condensate confined in a finite-depth potential well under a density-dependent gauge field. The interplay of the finite-depth potential well and the gauge field results in rich chiral dynamics. When the external potential is strong, coherent chiral collective dynamics, i.e. , chiral breathing dynamics accompanied by the dipole dynamics emerges. The wave packet in the well undergoes periodic directional-dependent compression/expansion. Notably, this chiral dynamics leads to the emergence of a Rabi-like oscillation of particles between the inside and outside well, providing an effective route to investigate the Rabi oscillation in the system. In a weak external potential well, the gauge field dominates and chiral tunneling and diffusion dynamics take place. Particularly, when diffusion and collapse coexist, a chiral moving soliton is generated, which plays a key role for coherent chiral quantum transport.Abstract We investigate chiral quantum dynamics of a Bose-Einstein condensate confined in a finite-depth potential well under a density-dependent gauge field. The interplay of the finite-depth potential well and the gauge field results in rich chiral dynamics. When the external potential is strong, coherent chiral collective dynamics, i.e. , chiral breathing dynamics accompanied by the dipole dynamics emerges. The wave packet in the well undergoes periodic directional-dependent compression/expansion. Notably, this chiral dynamics leads to the emergence of a Rabi-like oscillation of particles between the inside and outside well, providing an effective route to investigate the Rabi oscillation in the system. In a weak external potential well, the gauge field dominates and chiral tunneling and diffusion dynamics take place. Particularly, when diffusion and collapse coexist, a chiral moving soliton is generated, which plays a key role for coherent chiral quantum transport.

Europhysics Letters (EPL)Sep 22, 20260 citations

We analyze the time evolution of a magnetic excitation in a spin-

\frac{1}{2}

antiferromagnetic Heisenberg chain after a quantum quench. By a proper modulation of the magnetic exchange coupling, we prepare a static soliton of total spin

\frac{1}{2}

as an initial spin state. Using bosonization and a numerical time-dependent density matrix renormalization group algorithm, we show that the initial excitation evolves to a state composed of two counterpropagating chiral states, which interfere to yield $\ensuremath{\langle}{S}^{z}\ensuremath{\rangle}=\frac{1}{4}$ for each mode. We find that these dynamically generated states remain considerably stable as time evolution is carried out. We propose spin-Peierls materials and ultracold-atom systems as suitable experimental scenarios in which to conduct and observe this mechanism.