Fractional photon-assisted tunneling for Bose-Einstein condensates in a double well

TL;DR

This paper investigates fractional photon-assisted tunneling in Bose-Einstein condensates within a double well, revealing quantum resonances explained through N-particle quantum dynamics rather than mean-field non-linearity.

Contribution

It provides an analytical explanation for fractional photon resonances in few-particle quantum systems, challenging the notion that non-linearity is necessary for such phenomena.

Findings

Fractional photon resonances occur even at N=2 particles.

Analytic calculations explain the origin of these resonances.

Resonances are not limited to half-integer photon values.

Abstract

Half-integer photon-resonances in a periodically shaken double well are investigated on the level of the N-particle quantum dynamics. Contrary to non-linear mean-field equations, the linear N-particle Schrodinger equation does not contain any non-linearity which could be the origin of such resonances. Nevertheless, analytic calculations on the N-particle level explain why such resonances can be observed even for particle numbers as low as N = 2. These calculations also demonstrate why fractional photon resonances are not restricted to half-integer values.