# Non-linear optical response of the excited Laughlin liquid

## TL;DR

This paper reports the experimental observation of a nonlinear optical response in the excited Laughlin liquid at filling factor 1/3, caused by coherent anti-Stokes-Stokes scattering, revealing new insights into its optical properties.

## Contribution

It introduces the first experimental construction of neutral excitations in the Laughlin liquid and demonstrates their role in nonlinear optical phenomena.

## Key findings

- Nonlinear optical response with quadratic dependence on excitation power
- Observation of coherent anti-Stokes-Stokes scattering in the Laughlin liquid
- Excitations induce measurable changes in optical reflection

## Abstract

An ensemble of neutral excitations is constructed experimentally in the Laughlin liquid at the electron filling factor 1/3. The excitations are found to induce a nonlinear optical response, manifested as a quadratic dependence of the reflection signal on the excitation power. The reported experimental results indicate that the observed effect is due to the contribution of the coherent anti-Stokes-Stokes scattering of light from the excited Laughlin liquid.