Backward resonant four-wave mixing by quantum interference

Abstract

We report on an experimental observation of backward resonant four-wave mixing by quantum interference We derive the theory of four wave mixing and confirm that the highest conversion efficiency of forward four-wave mixing is 25% However the highest conversion efficiency of backward resonant four-wave mixing can reach about 97% when optical density approaches to 250 In our research we use N-type four energy levels system in cold rubidium atom to proceed backward resonant four-wave mixing experiments By fixing the intensity of coupling light intensity at 2 3 mW/cm2 and 4 7 mW/cm2 we alter the Rabi frequency of driving light to search the highest conversion efficiency The experimental result is that the conversion efficiency can reach 41 3% when systematic parameters are optical density equal to 48 coupling light intensity at 2 3 mW/cm2 and driving light intensity at 1 2 mW/cm2 Although this consequence dose not achieve the maximum conversion efficiency predicted by theoretical model it approve that the conversion efficiency of resonant backward four-wave mixing can breakthrough the highest efficiency of resonant forward four-wave mixing which is 25%

Date of Award	2016 Sept 7
Original language	English
Supervisor	Yong-Fan Chen (Supervisor)