论文信息 - Depolarization degree of picosecond radially polarized beam induced by non-radially symmetrical pumping during power amplification

Depolarization degree of picosecond radially polarized beam induced by non-radially symmetrical pumping during power amplification

The effect of the gain medium planar shear stress, induced by non-radially symmetrical pumping during power amplification process, on the depolarization of radially polarized beam was analyzed in detail. For radially polarized beam, theoretical simulation had showed that the non-radial distribution of planar shear stress led to the different depolarization in different polarization directions, that the depolarization of the direction of 45° and 135° is five times more serious than that of 0° and 90°. In the following experiment, the radially polarized seed beam with a repetition rate of 1 kHz, an average power of 5 W and a pulse width of 100 ps was single-propagating double-rod Nd:YAG laser amplifier. Each rod was surrounded by three diode-pumped arrays with an angle of 120°. During the amplification process, the depolarization degree of radially polarized beam was 6.73%, which was obtained by measuring the difference between the power of the two beams transmitted and reflected by the analyzer TFP. The power of amplified radially polarized beam was 15.17 W with the purity of 89.3% and M2 of 3.95.

Ce Yang | Meng Chen | Hongpan Peng

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