Abstract We study the correlation between an impurity and a small ensemble of bosonic particles in one dimension. Our study analyzes the one-body density matrix and calculates the corresponding von Neumann entanglement entropy as a function of the interaction strength between the impurity and the bosons when all particles have the same mass. We show that the entropy grows very fast for small and moderate interaction strength and then increases slowly toward the strongly interacting regime. Then we study the effect over the quantum correlations of a mass imbalance between the impurity and the bosons. In the strongly interacting case, we discover that when the impurity is much heavier than the bosons, then we have the least possible correlation. However, the entropy tops its maximum when the mass ratio is between 3 and 4 in the case where there are four bosonic particles and then falls off to its minimum for higher mass imbalance.Abstract We study the correlation between an impurity and a small ensemble of bosonic particles in one dimension. Our study analyzes the one-body density matrix and calculates the corresponding von Neumann entanglement entropy as a function of the interaction strength between the impurity and the bosons when all particles have the same mass. We show that the entropy grows very fast for small and moderate interaction strength and then increases slowly toward the strongly interacting regime. Then we study the effect over the quantum correlations of a mass imbalance between the impurity and the bosons. In the strongly interacting case, we discover that when the impurity is much heavier than the bosons, then we have the least possible correlation. However, the entropy tops its maximum when the mass ratio is between 3 and 4 in the case where there are four bosonic particles and then falls off to its minimum for higher mass imbalance.

arXiv:1512.03367Journal of Physics B Atomic Molecular and Optical PhysicsMar 17, 201618 citations

Classical and quantum aspects of strongly interacting one-dimensional systems

Shimul Akhanjee

Jan 1, 20080 citations

Strongly Interacting Quantum Systems in Low Dimensions.

Thomas Edward Blum

Jan 1, 19910 citations

High-temperature transport in the one-dimensional mass-imbalanced Fermi-Hubbard model

Thomas G. Kiely, Erich J. Mueller

We study transport in the one-dimensional mass-imbalanced Fermi-Hubbard model in the high-temperature limit, focusing on the case of strong interactions. Prior theoretical and experimental investigations have revealed unconventionally long transport timescales, with complications due to strong finite-size effects. We compute the dynamical current-current correlation function directly in the thermodynamic limit using infinite tensor network techniques. We show that transport in the strong-imbalance limit is dominated by AC resonances, which we compute with an analytic expansion. We study the dephasing of these resonances with mass imbalance, $\ensuremath{\eta}$. In the small-imbalance limit, the model is nearly integrable. We connect these unusual limits by computing the DC conductivity and transport decay time as a function of $\ensuremath{\eta}$ and the interaction strength $U/t$ . We propose an experimental protocol to measure these correlation functions in cold atom experiments.We study transport in the one-dimensional mass-imbalanced Fermi-Hubbard model in the high-temperature limit, focusing on the case of strong interactions. Prior theoretical and experimental investigations have revealed unconventionally long transport timescales, with complications due to strong finite-size effects. We compute the dynamical current-current correlation function directly in the thermodynamic limit using infinite tensor network techniques. We show that transport in the strong-imbalance limit is dominated by AC resonances, which we compute with an analytic expansion. We study the dephasing of these resonances with mass imbalance, $\ensuremath{\eta}$. In the small-imbalance limit, the model is nearly integrable. We connect these unusual limits by computing the DC conductivity and transport decay time as a function of $\ensuremath{\eta}$ and the interaction strength $U/t$. We propose an experimental protocol to measure these correlation functions in cold atom experiments.

arXiv:2404.08076Physical Review AJun 12, 20246 citations

Mass-imbalance-induced structures of binary atomic mixtures in box potentials

Bishal Parajuli, Daniel Pęcak, Chih-Chun Chien

We consider the ground states of binary atomic boson-boson and fermion-fermion mixtures confined in one-dimensional box potentials by simulating the systems using few-body models with $\ensuremath{\delta}$-function interactions and many-body models with density-density interactions. For boson-boson mixtures with strong interspecies repulsion, both models show sandwiched structures in the presence of mass imbalance but not in the equal-mass case. The structural difference between equal-mass and mass-imbalanced systems is due to the minimization of the interaction energy and the kinetic energies from the density distortion at the hard walls and at the phase-separation interface. The mass imbalance adjusts the kinetic energies and causes the lighter species to avoid the hard walls. For fermion-fermion mixtures, few-body simulations show mass-imbalance-induced structural changes in the strong-repulsion regime, while many-body simulations show two-chunk phase separation due to the strong bulk kinetic energy. For equal-mass mixtures with strong interspecies repulsion, the few-body and many-body models predict different structures because of the different treatments of kinetic and interaction energies.We consider the ground states of binary atomic boson-boson and fermion-fermion mixtures confined in one-dimensional box potentials by simulating the systems using few-body models with $\ensuremath{\delta}$-function interactions and many-body models with density-density interactions. For boson-boson mixtures with strong interspecies repulsion, both models show sandwiched structures in the presence of mass imbalance but not in the equal-mass case. The structural difference between equal-mass and mass-imbalanced systems is due to the minimization of the interaction energy and the kinetic energies from the density distortion at the hard walls and at the phase-separation interface. The mass imbalance adjusts the kinetic energies and causes the lighter species to avoid the hard walls. For fermion-fermion mixtures, few-body simulations show mass-imbalance-induced structural changes in the strong-repulsion regime, while many-body simulations show two-chunk phase separation due to the strong bulk kinetic energy. For equal-mass mixtures with strong interspecies repulsion, the few-body and many-body models predict different structures because of the different treatments of kinetic and interaction energies.

arXiv:1906.03573Physical Review ADec 9, 201910 citations

U/t

. We propose an experimental protocol to measure these correlation functions in cold atom experiments.