Polariton-generated intensity squeezing in semiconductor micropillars

Abstract

The generation of squeezed and entangled light fields is a crucial ingredient for the implementation of quantum information protocols. In this context, semiconductor materials offer a strong potential for the implementation of on-chip devices operating at the quantum level. Here we demonstrate a novel source of continuous variable squeezed light in pillarshaped semiconductor microcavities in the strong coupling regime. Degenerate polariton four-wave mixing is obtained by exciting the pillar at normal incidence. We observe a bistable behaviour and we demonstrate the generation of squeezing near the turning point of the bistability curve. The confined pillar geometry allows for a larger amount of squeezing than planar microcavities due to the discrete energy levels protected from excess noise. By analysing the noise of the emitted light, we obtain a measured intensity squeezing of 20.3%, inferred to be 35.8% after corrections.

Spatial multistability induced by cross interactions of confined polariton modes

“…The bistability and spinor multistability of a microcavity polariton have been extensively studied both theoretically [16][17][18][19][20][21][22] and experimentally [23][24][25][26][27][28][29][30][31][32]. It relies on exciting the microcavity using a laser blue detuned with respect to the lower polariton branch (LP) and to measure the transmitted laser intensity.…”

Polariton lasing in high-quality selenide-based micropillars in the strong coupling regime

“…4 Refined etching and microstructuring techniques have been developed for GaAs-based microcavity, allowing the fabrication of high quality micropillars, 5,6 mesas, 7 as well as advanced polaritonic circuits elements like waveguides, interferometers, optical gates, [8][9][10] and lattices with direct applications for quantum simulations. [11][12][13][14][15] This approach is likely to be successful in the upcoming years; however, for practical use, its drawback is to be stuck to cryogenic temperatures. A way around this problem is the use of large bandgap materials, where the exciton binding energy is larger, and hence stable at room temperature.…”

Simple model for interactions and corrections to the Gross-Pitaevskii equation

“…Our results apply also to novel condensates of molecules [13,14,20], photons [21], and polaritons [22,23] where the correction to the GPE may be larger. There are other corrections to the GPE, for example, the Lee-YangHuang (LYH) correction [1] which is typically larger than the correction that was considered here and is fundamentally of a different origin, as it depends on the density of particles while the correction (50) does not depend on this quantity.…”