Observations of complex frequency comb structure in a harmonically-pumped femtosecond optical parametric oscillator

23rd International Laser Physics Workshop

McCracken, Richard A.^1 ; Balskus, Karolis^1 ; Zhang, Zhaowei^1 ; Reid, Derryck T.^1

Scottish Universities Physics Alliance (SUPA), Institute of Photonics and Quantum Sciences, Heriot Watt University, Riccarton, Edinburgh

EH14 4AS, United Kingdom^1

关键词: Carrier-envelope;    Complex frequency;    Femtosecond optical parametric oscillators;    Heterodyne measurement;    Pump laser;    Ti:sapphire;    Tunable frequency;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/594/1/012004/pdf
DOI  :  10.1088/1742-6596/594/1/012004

来源: IOP

【 摘 要 】

Various schemes allow femtosecond optical parametric oscillators to produce pulses at harmonics of their pump laser repetition frequency, each apparently offering the possibility of generating widely-spaced, tunable frequency combs. Using a 100-MHz Ti:sapphire pump laser, we have compared two alternative optical parametric oscillator architectures, both leading to 300-MHz pulses but one configured in a cavity three times shorter than the pump laser and the other in a cavity one-third longer. Heterodyne measurements between the pump and each of these two systems show that they possess different carrier-envelope offset characteristics, with implications on the coherence and stabilization of the resulting combs.