Phase-conjugate Physics

M. C. Gower

Robert K. Tyson, Benjamin W. Frazier

J. A. Tataronis, Bahaa E. A. Saleh

The generation of phase conjugated replicas of optical signals has been the subject of many theoretical and experimental studies. Phase conjugation of harmonic signals is a byproduct of certain nonlinear processes such as degenerate four- wave mixing and stimulated Brillouin scattering. Although conjugation of steady signals is well established, the possibility and the effectiveness of conjugating unsteady signals remain largely unexplored. When the envelope of an optical signal varies, new physical phenomena in the conjugation process arise. As previously shown,1 dispersion in the conjugation process distorts the phase conjugate replica of a pulsed signal. Distortion appears even if the response of the medium to the applied optical signal is instantaneous.

Trevor J. Hall

Nicolas J. Cerf, S. Iblisdir

The phase conjugation of an unknown Gaussian state cannot be realized perfectly by any physical process. A heuristic argument is used to derive a tight lower bound on the noise that must be introduced by an approximate phase conjugation operation. A universal transformation achieving the optimal imperfect phase conjugation is then presented, which is the continuous counterpart of the universal-NOT transformation for quantum bits. In addition, it is shown that more information can be encoded into a pair of conjugate Gaussian states than by using the same state twice.

V. I. Kislenko, A. D. Lomakin

The spatiotemporal characteristics of nonlinear optical adaptive processes with the use of the effective reflectance of a phase-conjugate (PC) mirror based on the stimulated scattering of light or three-wave mixing are considered. The efficiency of the use of this physical parameter for studying the characteristics of PC mirrors in the case of inertialless nonlinearity is demonstrated by the example of phase conjugation of magnetostatic waves.