Development of Soft X-ray Frequency Modulator with Surface Plasmonic Device

• Main Authors: Tai-Yu Chen, 陳泰佑
• Other Authors: Jiunn-Yuan Lin
• Format: Others
• Language: en_US
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/16420176822471574499

碩士 === 國立中正大學 === 物理學系暨研究所 === 103 === In optical frequency modulations, acousto-optical modulator (AOM) is one of the important applications to demonstrate such nonlinear effect. Based on the momentum and energy conservation, frequency mixing in AOM is achieved by the interaction of photons and phonons. In the development of x-ray wave-mixing techniques, x-ray sum frequency generation (SFG) has been demonstrated by the interaction of x-ray photons and spatial charges induced by infrared photons in recent researches. The x-ray photons scattered by the oscillating charges at a specific frequency obtain the extra energy in the medium and make x-ray SFG possible. The purpose of this thesis is to develop an innovative soft x-ray frequency modulator based on the interaction of soft x-ray photons and surface plasmons. In this experiment, we propose to utilize an infrared laser to excite surface plasma wave on the surface of a tailor-made aluminum grating and irradiate the grating with a high harmonic generation (HHG) beam. The transmitted HHG is detected by a new design flat field spectrometer (FFS) to resolve the phenomenon of frequency modulation. In this experiment, we can not find any experimental signal from frequency modulations of soft x-rays due the instability of HHG source. However, we have successfully fabricated the free-standing grating for surface plasmon generations, measured the coupling efficiency of the grating and estimated the energy conversion efficiency of soft x-ray SFG. These results will be beneficial to achieve soft x-ray frequency modulation in the following experiment. Key Words: Surface Plasmon, Soft X-ray, Frequency Modulator