We investigate entanglement dynamics in the antiferromagnetic Heisenberg model in two dimensions following a spatially anisotropic quench of the exchange interactions. Opposed to established results in one dimension, the magnon quasiparticles show an initial growth of entanglement dynamics that does not depend on the system size and is governed by the oscillation period of the exchange interaction. This is much faster than the highest quasiparticle velocity, which we explain by the dominance of the intrinsic entanglement of short wavelength non-propagating magnon-pairs. Furthermore, by adopting the neural quantum states, we provide numerical evidence that this behavior survives even in the presence of strong magnon-magnon interactions, suggesting new avenues for manipulating entanglement dynamics in quantum materials.We investigate entanglement dynamics in the antiferromagnetic Heisenberg model in two dimensions following a spatially anisotropic quench of the exchange interactions. Opposed to established results in one dimension, the magnon quasiparticles show an initial growth of entanglement dynamics that does not depend on the system size and is governed by the oscillation period of the exchange interaction. This is much faster than the highest quasiparticle velocity, which we explain by the dominance of the intrinsic entanglement of short wavelength non-propagating magnon-pairs. Furthermore, by adopting the neural quantum states, we provide numerical evidence that this behavior survives even in the presence of strong magnon-magnon interactions, suggesting new avenues for manipulating entanglement dynamics in quantum materials.

Dec 23, 20190 citations

Ultrafast entanglement dynamics and spreading of quantum correlations in two-dimensional antiferromagnets

Giammarco Fabiani, Johan H. Mentink

We numerically study the real space-time dynamics of magnon pairs in the two-dimensional antiferromagnetic Heisenberg model after short perturbations of the exchange interaction. Analogous to the dynamics following quantum quenches in one dimension, we find ultrafast light-cone like spreading of quantum spin correlations. Interestingly, the spreading speed is larger than can be expected from the highest magnon or spinon group velocities. Opposed to results in one dimension, the evolution of entanglement is not directly linked to the spreading and dictated by the coherent dynamics of nearest neighbour correlations. We show that this enables coherent control of both phase and amplitude of entanglement oscillations. All results are obtained with the recently proposed neural quantum states.We numerically study the real space-time dynamics of magnon pairs in the two-dimensional antiferromagnetic Heisenberg model after short perturbations of the exchange interaction. Analogous to the dynamics following quantum quenches in one dimension, we find ultrafast light-cone like spreading of quantum spin correlations. Interestingly, the spreading speed is larger than can be expected from the highest magnon or spinon group velocities. Opposed to results in one dimension, the evolution of entanglement is not directly linked to the spreading and dictated by the coherent dynamics of nearest neighbour correlations. We show that this enables coherent control of both phase and amplitude of entanglement oscillations. All results are obtained with the recently proposed neural quantum states.

Dec 23, 20199 citations

Supermagnonic Propagation in Two-Dimensional Antiferromagnets

Giammarco Fabiani, M. D. Bouman, Johan H. Mentink

We investigate the propagation of magnons after ultrashort perturbations of the exchange interaction in the prototype two-dimensional Heisenberg antiferromagnet. Using the recently proposed neural quantum states, we predict highly anisotropic spreading in space constrained by the symmetry of the perturbation. Interestingly, the propagation speed at the shortest length scale and timescale is up to 40% higher than the highest magnon velocity. We argue that the enhancement stems from extraordinary strong magnon-magnon interactions, suggesting new avenues for manipulating information transfer on ultrashort length scales and timescales.We investigate the propagation of magnons after ultrashort perturbations of the exchange interaction in the prototype two-dimensional Heisenberg antiferromagnet. Using the recently proposed neural quantum states, we predict highly anisotropic spreading in space constrained by the symmetry of the perturbation. Interestingly, the propagation speed at the shortest length scale and timescale is up to 40% higher than the highest magnon velocity. We argue that the enhancement stems from extraordinary strong magnon-magnon interactions, suggesting new avenues for manipulating information transfer on ultrashort length scales and timescales.

arXiv:2101.10945Physical Review LettersAug 25, 202122 citations

Temporal Entanglement, Quasiparticles, and the Role of Interactions

Giacomo Giudice, Giuliano Giudici, Michael Sonner +4 more

In quantum many-body dynamics admitting a description in terms of noninteracting quasiparticles, the Feynman-Vernon influence matrix (IM), encoding the effect of the system on the evolution of its local subsystems, can be analyzed exactly. For discrete dynamics, the temporal entanglement (TE) of the corresponding IM satisfies an area law, suggesting the possibility of an efficient representation of the IM in terms of matrix-product states. A natural question is whether integrable interactions, preserving stable quasiparticles, affect the behavior of the TE. While a simple semiclassical picture suggests a sublinear growth in time, one can wonder whether interactions may lead to violations of the area law. We address this problem by analyzing quantum quenches in a family of discrete integrable dynamics corresponding to the real-time Trotterization of the interacting XXZ Heisenberg model. By means of an analytical solution at the dual-unitary point and numerical calculations for generic values of the system parameters, we provide evidence that, away from the noninteracting limit, the TE displays a logarithmic growth in time, thus violating the area law. Our findings highlight the nontrivial role of interactions, and raise interesting questions on the possibility to efficiently simulate the local dynamics of interacting integrable systems.In quantum many-body dynamics admitting a description in terms of noninteracting quasiparticles, the Feynman-Vernon influence matrix (IM), encoding the effect of the system on the evolution of its local subsystems, can be analyzed exactly. For discrete dynamics, the temporal entanglement (TE) of the corresponding IM satisfies an area law, suggesting the possibility of an efficient representation of the IM in terms of matrix-product states. A natural question is whether integrable interactions, preserving stable quasiparticles, affect the behavior of the TE. While a simple semiclassical picture suggests a sublinear growth in time, one can wonder whether interactions may lead to violations of the area law. We address this problem by analyzing quantum quenches in a family of discrete integrable dynamics corresponding to the real-time Trotterization of the interacting XXZ Heisenberg model. By means of an analytical solution at the dual-unitary point and numerical calculations for generic values of the system parameters, we provide evidence that, away from the noninteracting limit, the TE displays a logarithmic growth in time, thus violating the area law. Our findings highlight the nontrivial role of interactions, and raise interesting questions on the possibility to efficiently simulate the local dynamics of interacting integrable systems.

arXiv:2112.14264Physical Review LettersJun 2, 202267 citations

Quench dynamics of entanglement in an open anisotropic spin- 12 Heisenberg chain

Jie Ren, Shiqun Zhu

The quantum entanglement dynamics of a one-dimensional spin- $1/2$ anisotropic $\mathit{XXZ}$ model is studied using the method of the adaptive time-dependent density-matrix renormalization group when two cases of quenches are performed in the system. An anisotropic interaction quench and the maximum number of domain walls of a staggered magnetization quench are considered. The dynamics of the pairwise entanglement between the nearest two qubits in the spin chain is investigated. The entanglement of the two spin qubits can be created and oscillates in both cases of the quench. The anisotropic interaction has a strong influence on the oscillation frequency of the entanglement.The quantum entanglement dynamics of a one-dimensional spin-$1/2$ anisotropic $\mathit{XXZ}$ model is studied using the method of the adaptive time-dependent density-matrix renormalization group when two cases of quenches are performed in the system. An anisotropic interaction quench and the maximum number of domain walls of a staggered magnetization quench are considered. The dynamics of the pairwise entanglement between the nearest two qubits in the spin chain is investigated. The entanglement of the two spin qubits can be created and oscillates in both cases of the quench. The anisotropic interaction has a strong influence on the oscillation frequency of the entanglement.

arXiv:1006.1417Physical Review AJan 21, 201010 citations

Entanglement entropy in a periodically driven quantum Ising ring

Tony J. G. Apollaro, G. Massimo Palma, Jamir Marino

We numerically study the dynamics of entanglement entropy, induced by an oscillating time periodic driving of the transverse field, $h(t)$ , of a one-dimensional quantum Ising ring. We consider several realizations of $h(t)$ , and we find a number of results in analogy with entanglement entropy dynamics induced by a sudden quantum quench. After a short-time relaxation, the dynamics of entanglement entropy synchronizes with $h(t)$ , displaying an oscillatory behavior at the frequency of the driving. Synchronization in the dynamics of entanglement entropy is spoiled by the appearance of quasirevivals which fade out in the thermodynamic limit, and which we interpret using a quasiparticle picture adapted to periodic drivings. We show that the time-averaged entanglement entropy in the synchronized regime obeys a volume law scaling with the subsystem's size. Such result is reminiscent of a thermal state or a generalized Gibbs ensemble, although the system does not heat up towards infinite temperature as a consequence of the integrability of the model.We numerically study the dynamics of entanglement entropy, induced by an oscillating time periodic driving of the transverse field, $h(t)$, of a one-dimensional quantum Ising ring. We consider several realizations of $h(t)$, and we find a number of results in analogy with entanglement entropy dynamics induced by a sudden quantum quench. After a short-time relaxation, the dynamics of entanglement entropy synchronizes with $h(t)$, displaying an oscillatory behavior at the frequency of the driving. Synchronization in the dynamics of entanglement entropy is spoiled by the appearance of quasirevivals which fade out in the thermodynamic limit, and which we interpret using a quasiparticle picture adapted to periodic drivings. We show that the time-averaged entanglement entropy in the synchronized regime obeys a volume law scaling with the subsystem's size. Such result is reminiscent of a thermal state or a generalized Gibbs ensemble, although the system does not heat up towards infinite temperature as a consequence of the integrability of the model.

arXiv:1603.03579Physical review. B./Physical review. BOct 12, 201618 citations

The quantum entanglement dynamics of a one-dimensional spin-

1/2

anisotropic

\mathit{XXZ}

model is studied using the method of the adaptive time-dependent density-matrix renormalization group when two cases of quenches are performed in the system. An anisotropic interaction quench and the maximum number of domain walls of a staggered magnetization quench are considered. The dynamics of the pairwise entanglement between the nearest two qubits in the spin chain is investigated. The entanglement of the two spin qubits can be created and oscillates in both cases of the quench. The anisotropic interaction has a strong influence on the oscillation frequency of the entanglement.

We numerically study the dynamics of entanglement entropy, induced by an oscillating time periodic driving of the transverse field,

h(t)

, of a one-dimensional quantum Ising ring. We consider several realizations of

h(t)

, and we find a number of results in analogy with entanglement entropy dynamics induced by a sudden quantum quench. After a short-time relaxation, the dynamics of entanglement entropy synchronizes with

h(t)

, displaying an oscillatory behavior at the frequency of the driving. Synchronization in the dynamics of entanglement entropy is spoiled by the appearance of quasirevivals which fade out in the thermodynamic limit, and which we interpret using a quasiparticle picture adapted to periodic drivings. We show that the time-averaged entanglement entropy in the synchronized regime obeys a volume law scaling with the subsystem's size. Such result is reminiscent of a thermal state or a generalized Gibbs ensemble, although the system does not heat up towards infinite temperature as a consequence of the integrability of the model.