MULTIPLE-REFLECTION LAMBDA 4 PHASE-SHIFTER - A VIABLE ALTERNATIVE TO GENERATE CIRCULAR-POLARIZED SYNCHROTRON-RADIATION/

We propose the use of a multiple-reflection polarizer as a highly effe ctive tool to generate circular-polarized synchrotron radiation by uti lizing the phase difference in the s- and p-components of multiple-ref lected light. In the energy range hnu = 8-100 eV, a quadruple reflecto r can be optimized either in the degree of circular polarization P(cir c) or in the modified throughput TP(circ)2. A linear undulator/quadrup le reflector polarizer system is much more effective than the crossed- field undulator concept. In addition to the high throughput, a multipl e reflector used as a post-polarizer for monochromatized light provide s an easy way to control and modulate the state of polarization P(circ ). The proposed concept of converting linearly polarized monochromatic light into circular light does not encounter the potential dephasing problems intrinsic to the other alternatives. Extensive model calculat ions to optimize the figure of merit TP(circ)2 are presented, and a me chanical design of a prototype quadruple polarizer presently under con struction at SRC is discussed in detail.