POLARIZATION-DEPENDENT CAVITY RING DOWN SPECTROSCOPY

We here theoretically outline and experimentally demonstrate that pola rization spectroscopy can be combined with cavity ring down (CRD) spec troscopy, thereby retaining the specific advantages of both techniques . The b(1) Sigma(g)(+)(v'= 2) <-- X-3 Sigma(g)(-)(v'' = 0) transition of molecular oxygen around 628 nm is used to demonstrate the possibili ty to selectively measure either the polarization-dependent absorption or the resonant magneto-optical rotation of gas-phase molecules in th e appropriate setup. Just as in CRD absorption spectroscopy, where the rate of absorption is measured, in the here presented polarization-de pendent CRD (PDCRD) detection scheme the rate of polarization rotation is measured, which enables the polarization rotation to be quantitati vely determined. Apart from studying electro-optic and magneto-optic p henomena on gas-phase species, the PDCRD detection scheme is demonstra ted to be applicable to the study of magneto-optical rotation in trans parent solid samples as well. (C) 1997 American Institute of Physics.