Bl. Lawrence et al., LARGE PURELY REFRACTIVE NONLINEAR INDEX OF SINGLE-CRYSTAL P-TOLUENE SULFONATE (PTS) AT 1600 NM, Electronics Letters, 30(5), 1994, pp. 447-448
Z-scan measurements at 1600 nm on single-crystal PTS (p-toluene sulfon
ate) with single, 65 ps pulses gave a complex nonlinear refractive ind
ex coefficient of n2 = 2.2(+/-0.3) x 10(-12)cm2/W at 1 GW/cm2 and alph
a2 < 0.5cm/GW. This is the first highly nonlinear, organic material to
satisfy the conditions imposed by the figures of merit.