Linearisation of atomic magneto-optic rotation signals at large offset angles of the analyser

Abstract

A high-frequency modulation technique for use in magneto-optic rotation (MOR) spectroscopy is described which allows the polariser and analyser to be offset by angles up to about π/4. This adaptation of the MOR technique gives signal to atomiser emission background ratios which are of the order of those observed in conventional atomic absorption spectrometry (AAS) measurements, and leads to a corresponding degree of tolerance towards atomiser emission. The advantages of background correction ability and availability of both dichroic and birefringent signals are retained. The modulation technique has a further advantage in that it allows the shot-noise limit to be reached with a minimum of technical difficulty.