It is shown that a nearly degenerate four-wave mixing process is capable of yielding a real-time optical bandpass filter. The filter has a large field of view and is capable of providing an amplified bandpass. Moreover, the conjugate nature of the output field can be utilized to increase the signal-to-noise ratio of the device. For a 1-cm interaction length in a nondispersive medium, the optical bandpass at 5000 Å can be varied from ~9 GHz down to the linewidth of the exciting laser.
© 1978 Optical Society of America
Original Manuscript: June 29, 1978
Published: December 1, 1978
David M. Pepper and Richard L. Abrams, "Narrow optical bandpass filter via nearly degenerate four-wave mixing," Opt. Lett. 3, 212-214 (1978)