• Korean Journal of Optics and Photonics
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• v.17 no.6
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• pp.556-563
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• 2006

We present a comprehensive study of a chirped pulse Ti:sapphire regenerative amplifier system operating at 1 kHz. Main constituents of the system are described in detail. The amplifier stage was first converted to a repetition rate-tunable kHz gain-switched nanosecond Ti:sapphire laser. Operation characteristics at different repetition rates such as build-up times of laser pulses, pump power-dependent output powers and pulse durations, damage thresholds, and tunability ranges were studied. Based on the results achieved, the switching time of the Pocket's cell used and the round trip numbers in the regenerative amplifier were optimized at 1 kHz. The output pulses with a pulse width of 50fs from a home-made Ken lens mode-locked Ti:sapphire oscillator were used as seed pulses. The pulses were expanded to 120ps in a grating stretcher prior to coupling into the 3-mirror amplifier cavity. After amplification and recompression, a stable 1kHz Ti:sapphire regenerative amplifier system, which delivers 85-fs, $320-{\mu}J$ pulses, was fully constructed.

• Proceedings of the Optical Society of Korea Conference
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• 2002.07a
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• pp.226-227
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• 2002

처프펄스증폭(CPA) 개념을 이용한 티타늄 사파이어 레이저는 고출력 펨토초 펄스 생성에서 표준적인 시스템이며, 현재 수 kHz의 반복률에서 TW 급의 출력을 가지는 시스템들이 개발되어 사용 중이다.(1) 그러나 증폭시에 나타나는 티타늄 사파이어 레이저 매질에서의 이득 좁아짐 효과 때문에 얻어지는 최소 펄스폭은 20 펨토초 수준으로 제한된다. 이러한 스펙트럼폭의 한계를 극복하기 위하여 hollow-fiber에서의 자체위상변조(SPM) 현상을 이용하여 500 nm 이상의 파장 영역에 걸친 continuum을 발생시키는 기술이 제안되었다. (중략)

• Optical Science and Technology
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• v.13 no.2
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• pp.29-38
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• 2009

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.34-35
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• 2003

펨토초 레이저의 개발은 커렌즈 모드록킹 (Kerr-lens mode-locking； KLM) 기술이 티타늄사파이어 이득매질에 적용되면서 1990년대에 들어 급격하게 이루어졌다. 구조가 간단하면서 안정적인 KLM 티타늄사파이어 레이저는 현재 펨토초 레이저 광원의 표준을 이루고 있으며, 처프펄스 증폭 (chirped-pulse amplification； CPA) 방식을 이용하여 소규모의 테라와트급 고출력 펨토초 레이저 제작에도 이용되고 있다. 특히, 1990년대 말에는 CPA 증폭단을 갖춘 KLM 티타늄사파이어 레이저가 상용화되면서 물리, 화학과 같은 기초 분야에서뿐만 아니라 의료용, 산업용으로도 활용이 확대되고 있다. (중략)

• Proceedings of the Optical Society of Korea Conference
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• 2005.07a
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• pp.318-319
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• 2005

• Korean Journal of Optics and Photonics
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• v.33 no.6
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• pp.260-266
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• 2022

A diffraction grating structure composed of two matching layers and two grating layers was formed, and a diffraction grating with high transmission diffraction efficiency in the -1st order was designed through an optimization technique. The designed diffraction grating had a transverse electric wave diffraction efficiency of 99.997% at the design center wavelength, and had a wavelength width of 80 nm and an incident angle width of 20.0° that maintained a diffraction efficiency of 95% or more. By performing the grating tolerance analysis, it was confirmed that the thickness tolerance for a diffraction efficiency of 95% or more was secured to at least 60 nm, and the diffraction efficiency could be maintained even in a trapezoidal shape with an internal angle of less than 10°.