Quantum theory of noise in phase conjugation by four-wave mixing in a two-level system

R. W. Schirmer, M. Y. Lanzerotti, A. L. Gaeta, G. S. Agarwal
1997 Physical Review A. Atomic, Molecular, and Optical Physics  
A quantum theory of nearly degenerate backward four-wave mixing in a two-level atomic system is developed. The theory is used to calculate the quantum noise produced by a phase-conjugate mirror based on this system. The results indicate that in the case of pure radiative broadening the ideal quantum-noise limit is reached for relatively small pump-wave strengths and for relatively large probe-pump and pump-resonance detunings, so that the phase-conjugate reflectivity is far from its maximum
more » ... rom its maximum value. Conversely, in the collisionally broadened case, operation closest to the quantum-noise limit occurs near the point of maximum reflectivity. ͓S1050-2947͑97͒03604-4͔
doi:10.1103/physreva.55.3155 fatcat:kq7h5hvq6fge7euqb5yz3jdonm