Stress-Tuning of Optical Rectification in Organic 4-N,N-dimethylamino-4'-N'-methyl-stilbazolium tosylate (DAST)

Abstract Optical rectification (OR) of organic 4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate (DAST) single crystal was investigated. The relation between the two tensor elements d33 and d32 of DAST was theoretically derived to be d32 = 2.29d33. In measurements, the amplitude of the OR voltage signal of a strain-relaxed DAST single crystal reached 980 mV, much higher than those achieved in the well-known ammonium dihydrogen phosphate (ADP) and potassium dihydrogen phosphate (KDP). Taking advantage of the good elasticity of organic crystals, we also succeeded in tuning the OR signal of DAST by external stress, opening a new route to its applications in nonlinear optics and sensing.