Numerical analysis of the effects of cross-correlated quantum noise terms in a single-mode laser

The effects of cross-correlation between the real and imaginary terms of quantum noise in a single-mode laser are investigated through robust numerical simulations. In comparison with the previous theoretical analyses [S.Z. Ke, et al., Phys. Lett. A 281 (2001) 113], in which the closed form of the laser intensity Langevin equation was derived and a first-order-like transition was predicted under approximative phase locking procedure, some interesting results are found as follows: (i) the laser phase locking undergoes a process as the cross-correlation strength varies from zero to unity. When the quantum noise terms are perfectly correlated, the phase can be universally locked to the most stable states. The mechanism of phase locking is revealed. (ii) The prediction of a first-order-like transition in the single-mode laser is confirmed by the numerical simulations, and the validity of the approximative phase locking procedure is evaluated.