Electron-hole liquid in GaP: N

The radiative recombination of the nitrogen-induced electron-hole liquid in GaP: N is observed. The liquid is formed by delocalization of excitons bound to nitrogen in crystals in which the nitrogen concentration exceeds ${10}^{17}$ ${\mathrm{cm}}^{-3\mathrm{}}$, and under intense band-gap or selective excitation into the lowest $J=1\mathrm{}$ state of the bound exciton ($A$ line). The observed binding energy is 17 meV relative to the free-exciton level. The liquid density is in the range of (1-4) × ${10}^{18}$ ${\mathrm{cm}}^{-3\mathrm{}}$ for excitation intensity varying in the range of ${10}^{14}$-${10}^{18}$ photons/${\mathrm{cm}}^2$/pulse.