Triphoton generation and heralded biphotons via spontaneous six-wave mixing in coherently driven cold atoms
Phys. Rev. A 112, 013706 – Published 7 July, 2025
DOI: https://doi.org/10.1103/5c5q-1tk8
Abstract
We investigate the generation of a triphoton state based on spontaneous six-wave mixing in cold atoms coherently driven by pumping, dressing, and coupling fields upon separate transitions. The designed energy-level structure largely suppresses linear absorption (Raman gain) of generated triphotons due to destructive interference (negligible excitation) and avoids stray biphotons arising from spontaneous four-wave mixing with appropriate atomic states and driving schemes. Numerical results show that two Stokes and one anti-Stokes photon, traveling respectively at the vacuum light speed and a reduced group velocity, can be simultaneously generated in a joint spectral region of two detunings exhibiting four resonances. Original third-order and reduced second-order time correlations of these photons suggest that one is an excellent messenger for heralding the existence of the other two, exhibiting a considerable generation rate and an obvious nonclassical feature.
