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arXiv · 1406.4949

Terahertz Generation in Lithium Niobate Driven by Ti:Sapphire Laser Pulses and its Limitations

Xiaojun Wu·Sergio Carbajo·Koustuban Ravi·Frederike Ahr·Giovanni Cirmi·Yue Zhou·Oliver D. Mücke·Franz X. Kärtner
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Abstract

We experimentally investigate the limits to 800 nm-to-terahertz (THz) energy conversion in lithium niobate at room temperature driven by amplified Ti:Sapphire laser pulses with tilted-pulse-front. The influence of the pump central wavelength, pulse duration, and fluence on THz generation is studied. We achieved a high peak efficiency of 0.12% using transform limited 150 fs pulses and observed saturation of the optical to THz conversion efficiency at a fluence of 15 mJ/cm2. We experimentally identify two main limitations for the scaling of optical-to-THz conversion efficiencies: (i) the large spectral broadening of the optical pump spectrum in combination with large angular dispersion of the tilted-pulse-front and (ii) free-carrier absorption of THz radiation due to multi-photon absorption of the 800 nm radiation.

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Xiaojun Wu, Sergio Carbajo, Koustuban Ravi, Frederike Ahr, Giovanni Cirmi, Yue Zhou, Oliver D. Mücke, Franz X. Kärtner. 2014-06-19. Terahertz Generation in Lithium Niobate Driven by Ti:Sapphire Laser Pulses and its Limitations. https://doi.org/10.1364/ol.39.005403

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