Quantum motion of an impurity through a medium at zero temperature in one spatial dimension
Mikhail Zvonarev (LPTMS, Université Paris-Sud)
I will report on a theoretical and experimental progress in understanding the dynamics of an impurity injected into a one-dimensional quantum liquid. I will show that the momentum distribution of the impurity subject to a constant external force exhibits characteristic Bragg reflections at the edge of an emergent Brillouin zone. As a consequence, the impurity exhibits periodic dynamics that is interpreted as Bloch oscillations, which arise even though the quantum liquid is translationally invariant. I will also discuss a quantum flutter phenomenon, whose essence is that the impurity injected into a liquid with some initial momentum sheds only a part of it to the background gas, and forms a correlated state that no longer decays in time; furthermore, if the initial momentum is large enough, the impurity undergoes long-lived oscillations.