High-order sideband effect with two-level atoms in a shaken optical lattice

TL;DR

This paper reports the experimental observation of high-order sideband effects in a shaken optical lattice with two-level atoms, revealing new dynamical regimes and mechanisms distinct from semiconductor analogs.

Contribution

The study demonstrates a novel regime where high-order sidebands are observed in a shaken optical lattice, supported by a theoretical model explaining the unique quantum dynamical effects.

Findings

Observation of high-order sideband effect (HSE) in shaken optical lattice.

HSE occurs under conditions where shaking rate exceeds linewidth but is below lattice frequency interval.

Theoretical model with analytical solution explains the experimental results.

Abstract

The system of cold two-level atoms inside an optical lattice potential has been used to simulate various models encountered in fundamental and condensed-matter physics. When the optical lattice is periodically shaken, some interesting dynamical effects were observed. In this work, by utilizing the ultra-narrow linewidth of the dipole-forbidden transition in $^{87}$Sr atoms loaded in a shaken optical lattice, we reach a new operation regime where the shaking rate is much larger than linewidth of the two-level transition but much smaller than the frequency interval of the harmonic lattice potential, which was not realizable before. Under such unique conditions, an interesting quantum dynamical effect, the high-order sideband effect (HSE), has been experimentally observed. All the results can be well explained by a developed theoretical model with analytical solution. This HSE is governed by different mechanism as the similar phenomenon observed in semiconductors and has unique characteristics.