Abstract

The investigation of nonlinear effects usually requires the use of a macroscopic medium and intense light fields. Commonly, the high field strength is realized by using short laser pulses or continuous wave (cw) excitation inside optical cavities. In recent years, there have been many studies on nonlinear phenomena in microscopic systems, all the way down to nanoparticles, where phase matching conditions no longer apply. In this presentation, we report on nonlinear optical effects involving only a single quantum emitter and cw light. In particular, we show coherent energy transfer from a strong pump beam to a weak probe beam via a four-wave mixing process. Indirect evidence of this effect had been previously observed by measuring the increase in fluorescence that occurs when the four-wave mixing condition is met [1]. Efficient coupling via tight focusing has now allowed us to directly measure the coherent amplification of the probe beam [2].

© 2015 IEEE