2016/02/17 by Neil J. Robinson, Robinson, Neil J., Jean-Sébastien Caux +3
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Opinion Dynamics and Social Influence #Quantum Gases (cond-mat.quant-gas) #Strong Light-Matter Interactions
paper · pdf · doi:10.48550/arxiv.1602.05532
openalex publication_date 2016/02/17 · openalex created_date 2022/10/01 · openalex updated_date 2026/07/28
We consider the non-equilibrium dynamics of two-component one dimensional\nquantum gases in the limit of extreme population imbalance where the minority\nspecies has but a single particle. We consider the situation where the gas is\nprepared in a state with a single spatially localized exciton: the single\nparticle of the minority species is spatially localized while the density of\nthe majority species in the vicinity of the minority particle sees a\ndepression. Remarkably, we are able to consider cases where the gas contains on\nthe order of N=100 particles, comparable to that studied in experiments on\ncold atomic gases. We are able to do by exploiting the integrability of the gas\ntogether with the observation that the excitonic state can be constructed\nthrough a simple superposition of exact eigenstates of the gas. The number of\nstates in this superposition, rather than being exponentially large in the\nnumber of particles, scales linearly with N.\n We study the evolution of such spatially localized states in both strongly\ninteracting Bose and Fermi gases. The behavior of the light cones when the\ninteraction strength and density of the gas is varied can be understood from\nexact results for the spin excitation spectrum in these systems. We argue that\nthe light cone in both cases exhibits scaling collapse. However unique to the\nBose gas, we show that the presence of gapped finite-momentum roton-like\nexcitations provide the Bose gas dynamics with secondary light cones.\n