Surface Selective Chiral Detection: A New Metrology Technique

The near chiral purity of the biosphere leads to a vast array of chiro-specific physiological responses. This chiro-specificity, in turn, gives rise to the need for the manufacturing of enantiomerically pure chiral chemicals, such as pesticides, pharmaceuticals, food additives, pigments, etc. Critical to the efficacy of both chiro-specific biology and chiro-synthesis/separation are the interfacial regions of chiral surface layers. Vescent Photonics proposes to develop an entirely new metrology technique designed to investigate chiral surface layers. The technique combines the established fields of optical activity (circular dichroism and optical rotary dispersion) for chiro-specificity with evanescent wave sensing for surface selectivity. The device employs a new polarization modulator, with demonstrated speeds of greater than 200 kHz and great potential for compact, and economic construction.