2 Search Results

We experimentally investigate four-wave mixing (FWM) in a diamond interaction scheme using ⁸⁵ Rb vapor, and identify the optimal conditions for joint amplification and relative intensity squeezing of two optical fields: one near the ⁸⁵ Rb D ₁ optical transition ( λ  = 794.6 nm) and the other in the telecom O-band ( λ  = 1324 nm). We achieved a reduction of relative intensity noise by up to 2.6 ± 0.4 dB compared with the shot noise level, signifying the non-classical quantum correlations. The observed level of intensity squeezing is primarily limited by the available pump laser power, which constrains the achievable FWM gain. Numerical simulations show good agreement with the experimental results.

Here, we report an experimental demonstration of anti-parity-time symmetric optical four-wave mixing in thermal rubidium vapor, where the propagation of probe and stokes fields in a double-Λ scheme is governed by a non-Hermitian Hamiltonian. We are particularly interested in studying quantum intensity correlations between the two fields near the exceptional point, taking into account loss and accompanied Langevin noise. Our experimental measurements of classical four-wave mixing gain and the associated two-mode relative-intensity squeezing are in reasonable agreement with the theoretical predictions.