Coherent beam combining (CBC) by active phase control could be useful for power scaling fiber-laser-pumped optical frequency converters like optical parametric oscillators (OPOs). We developed an indirect phase control approach based on the phase matching relation intrinsic to efficient nonlinear processes. Previously, we demonstrated coherent combining of second harmonic waves through real time active control of the phases of the fundamental waves, using high bandwidth fibered electro-optic phase modulators. In the case of this 2- wavelength process, it was possible to simultaneously combine both the fundamental and the second harmonic waves. In this paper, we present an experimental demonstration of coherent combining of difference frequency generators emitting an idler wave at 3400 nm. We confirm experimentally the theoretical prediction that through active phase control of the sole 1064 nm pump waves, it’s possible to coherently combine the idler waves efficiently. A residual phase error of 1/28th wave at 3400 nm is achieved, corresponding to an excellent combining efficiency. However, in such a 3-wavelength process, simultaneous combination of the signal and idler waves is not always feasible. This demonstration opens the way to mid-infrared OPO combining. We present the architectures of continuous wave OPOs we are working on.
P. Bourdon, R. Chtouki, A. Durécu, L. Lombard, C. Planchat, M. Raybaut, and A. Godard, "Coherent combining of difference frequency generators: experimental demonstration and application to optical parametric oscillators," Proc. SPIE 10902, Nonlinear Frequency Generation and Conversion: Materials and Devices XVIII, 109020L (Presented at SPIE LASE: February 06, 2019; Published: 4 March 2019); https://doi.org/10.1117/12.2509933.
Conference Presentations are recordings of oral presentations given at SPIE conferences and published as part of the proceedings. They include the speaker's narration with video of the slides and animations. Most include full-text papers. Interactive, searchable transcripts and closed captioning are now available for most presentations.
Search our growing collection of more than 18,000 conference presentations, including many plenaries and keynotes.