Nonlinear optical activity in chiral molecules: Surface second harmonic generation and nonlinear circular dichroism

Nonlinear optical activity in chiral molecules is investigated. We first examine the importance of the nonlocality of the light-matter interaction in optical activity and extend this concept to second-order (surface second harmonic generation) and third-order (nonlinear circular dichroism) nonlinear optical phenomena. Microscopic models are also discussed. Various phenomena derived from these considerations are demonstrated experimentally with specially-synthesized chiral molecules.