Polarizer-analyzer optics

The principles behind the design and operation of polarization-based optics for nuclear resonant scattering of synchrotron radiation are discussed. Wi th perfect single crystals and collimated X-rays emitted from undulator-bas ed third-generation synchrotron radiation sources, polarization-selective o ptics with a sensitivity of parts per billion can be obtained. A general ap proach to optical activity is introduced, and the polarization dependence o f the index of refraction is calculated for nuclear forward scattering for a medium with unidirectional symmetry. Some recent experimental results are reviewed and future applications are discussed.