Optical manipulation system for Steady State Microbunching in storage ring.

Steady State Microbunching (SSMB) is one of the schemes for generation of high average power coherent synchrotron radiation(CSR) in a storage ring. As the first proof-of-principle experiment has succeeded at the MLS storage ring in Berlin, it could be a promising candidate of kW level EUV source for lithography with the advantage of narrow linewidth, high power, collimated and clean beam. To satisfy the requirement of SSMB modulation field, the turn by turn phase must be stable and the field need be as high as ~MV/m over several meters of the modulation length. We have studied the effect on microbunch formation and maintenance of turn by turn phase with arbitrary phase jitter with noise spectrum from a commercially available relatively high-power continuous wave laser with a MW level enhancement cavity. The cases of synthesized field by multicolor laser field and adiabatic modulation are also considered. Compare with single color sheme under the same power, the microbunch length of 2-color scheme can be three times smaller while 3-color scheme can be six times smaller. Thus we can generate CSR at shorter wavelength with shorter microbunch length.