Phase sensitive two-mode squeezing and photon correlations from exciton superfluid in semiconductor electron-hole bilayer systems

Abstract

There have been experimental and theoretical studies on Photoluminescence (PL) from possible exciton superfluid in semiconductor electron-hole bilayer systems. However, the PL contains no phase information and no photon correlations, so it can only lead to suggestive evidences. It is important to identify smoking gun experiments which can lead to convincing evidences. Here we study two mode phase sensitive squeezing spectrum and also two photon correlation functions. We find the emitted photons along all tilted directions are always in a two mode squeezed state between k and − k. There are always two photon bunching, the photon statistics is super-Poissonian. Observing these unique features by possible future phase sensitive homodyne experiment and HanburyBrown-Twiss type of experiment could lead to conclusive evidences of exciton superfluid in these systems.

Coherence lengths in attractively interacting Fermi gases with spin-orbit coupling

“…In Refs. [32][33][34][35], the authors ignored the spins of the fermions and holes, therefore also the possible Rashba SOC. As shown at the end of [34], the bright excitons couple to the one-photon process with the polarization σ = ±.…”

“…Due to its short coherence ξ , high-temperature superconductors are near the BCS to BEC crossover, but still in the BCS side with a well-defined Fermi surface [29,31], so quantum fluctuation effects are large. The BCS to BEC crossover of exciton superfluids in an electron-hole semiconductor bilayer can be tuned by the exciton density [32][33][34][35]. The BCS to BEC crossovers of attractively interacting neutral fermions are tuned by sweeping across a Feshbach resonance [30].…”

“…II B for its definition) approaches 1. So they concluded that at a fixed scattering length at the BCS side (in the absence of SOC), the SOC drives a BCS to BEC crossover which is in a different class than the one without a SOC driven by the exciton density [32][33][34][35] or Feshbach resonance [30]. However, as shown in this paper, the Cooper-pair wave function is useful for illustration purposes only instead of being physical, so its overlap with the two-body wave function is not physical and cannot be measured experimentally.…”

Quantum magnetism of spinor bosons in optical lattices with synthetic non-Abelian gauge fields

“…The interesting phenomena of one central peak S +− u,U(1) (β, k) splits into two as tuning the gauge parameter β resembles those in the angle resolved photo emission spectrum (ARPS) S 1 (k, ω) as one tunes the momentum ( or energy ) in electron-hole semi-conductor bilayer [45][46][47] or the differential conductance dI(Q,V ) dV as tuning the in-plane magnetic field Q = 2πd φ0 B ||x in the bilayer quantum Hall systems at total filling factor ν T = 1 [48]. In all the three systems, there is a pinned flat regime in the corresponding tuning parameters β, k, Q before the single peak splits into two symmetric peaks with smaller heights.…”

Optical Bragg, atomic Bragg and cavity QED detections of quantum phases and excitation spectra of ultracold atoms in bipartite and frustrated optical lattices

“…This can be more easily realized inside a flat trap 55 or inside a harmonic trap with only one shell structure such as in Fig.12. It is constructive to compare with the photon-exciton coupling i k g(k)a † k b k + h.c. in the electron-hole bilayer (EHBL) system [63][64][65] where photons couple to the SF order parameter b k directly. Here the photons couple to both the density order parameter and also the valence bond order parameter instead of coupling to the SF order parameter directly.…”