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Ultra-Violet Optical Amplifier Based on Plasma-Core PCF

Optical amplifiers are an important key element in modern physics. For example, in optical communication, in order to transmit signal over long distance, they are inserted to compensate optical signal attenuation due to fiber loss. For system laser they are used as active gain medium. Today, optical amplifiers can be divided into two classes: doped fiber and solid-state amplifiers [1]. However, these conventional amplifiers are mainly limited to the visible and near infrared spectral range. This limitation is particularly acute in the ultra-violet (UV) range because of the lack of suitable materials for UV emission and optical guidance. Conversely, gas-filled hollow-core photonic crystal fiber (HCPCF) has successfully been extended to ionized gases by generating and micro-confining stable plasma using non-intrusive [2] and compact microwave surface-wave excitation configuration [3]. It was proven that with this new plasma-core PCF (PCPCF), one can emit radiation over a large spectrum including several lines in the UV and DUV [4].