Unidirectional amplification and shaping of optical pulses by three-wave mixing with negative phonons

A possibility to greatly enhance frequencyconversion efficiency of stimulated Raman scattering is shown by making use of extraordinary properties of threewave mixing of ordinary and backward waves. Such processes are commonly attributed to negative-index plasmonic metamaterials. This work demonstrates the possibility to replace such metamaterials that are very challenging to engineer by readily available crystals which support elastic waves with contra-directed phase and group velocities. The main goal of this work was to investigate specific properties of indicated nonlinear optical process in short-pulse regime and to show that it enables elimination of fundamental detrimental effect of fast damping of optical phonons on the process concerned. Among the applications is the possibility of creation of a family of unique photonic devices such as unidirectional Raman amplifiers and femtosecond pulse shapers with greatly improved operational properties. A. K. Popov (B) University of Wisconsin-Stevens Point, Stevens Point, WI 54481, USA e-mail: [email protected] A. K. Popov Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907, USA e-mail: [email protected] M. I. Shalaev · V. V. Slabko Siberian Federal University, 660041 Krasnoyarsk, Russian Federation S. A. Myslivets Institute of Physics of Russian Academy of Sciences, 660036 Krasnoyarsk, Russian Federation