Harmonics-assisted optical phase amplification with a self-mixing thin-slice Nd:GdVO4 laser operating in the self-induced skew cosh Gaussian mode

Kenju Otsuka; Seiichi Sudo

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arXiv · 2502.12597

Harmonics-assisted optical phase amplification with a self-mixing thin-slice Nd:GdVO4 laser operating in the self-induced skew cosh Gaussian mode

Kenju Otsuka·Seiichi Sudo

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Abstract

Harmonic-assisted phase amplification was achieved in a 300-micrometer-thick Nd:GdVO4 laser in the self-mixing interference scheme. The key event is the self-induced skew cosh Gaussian (e.g., skew-chG) mode oscillation in a thin-slice solid-state laser with wide-aperture laser-diode pumping. The skew-chG mode was proved to be formed by the phase-locking of nearly frequency-degenerate TEM00 and annular fields. The resultant modal-interference-induced gain modulation at the beat frequency between the two modal fields, which is far above the relaxation oscillation frequency, increased experimental self-mixing modulation bandwidth accordingly. Fifty-fold phase amplification was achieved in a strong optical feedback regime.

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Kenju Otsuka, Seiichi Sudo. 2025-02-18. Harmonics-assisted optical phase amplification with a self-mixing thin-slice Nd:GdVO4 laser operating in the self-induced skew cosh Gaussian mode. https://arxiv.org/abs/2502.12597

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