A new type of interferometer has been constructed that uses a beam splitter and two self-pumped BaTiO3 crystals as phase-conjugate reflectors in place of the usual interferometer mirrors. Counterpropagating beams of light are spontaneously generated between the two crystals, coupling the pair of phase conjugators. This optical oscillation locks the relative phase of the two phase-conjugate reflections such that they recombine at the beam splitter to form only a single beam as though they were truly time-reversed waves.
© 1985 Optical Society of America
M. D. Ewbank, P. Yeh, M. Khoshnevisan, and Jack Feinberg, "Time reversal by an interferometer with coupled phase-conjugate reflectors," Opt. Lett. 10, 282-284 (1985)