Jogy George

Thermal lens measurement technique in end-pumped solid state lasers: Application to diode-pumped microchip lasers

A simple derivation, which relates the thermal lens focal length in solid state lasers to pump power and a method for direct estimation of thermal lens focal length, is reported. This method is applicable to any type of stable resonator. The method is used for the measurement of the thermal lens focal length with an accuracy of 8% in an axially pumped microchip laser. The variation of focal length with pump power is also measured.

Single-frequency linear orthogonally polarized modes resulting in unidirectional traveling wave cavity green laser

Abstract. A narrow linewidth (∼8  MHz, instrument limited) CW green laser at 532 nm is demonstrated in linear orthogonally polarized modes resulting in an unidirectional travelling wave cavity using intracavity second-harmonic generation technique with >250-mW output power.

Beam quality degradation of a higher order transverse mode beam due to spherical aberration of a lens

An analysis of the increase in the beam-propagation factor, M2, of a higher order transverse mode beam caused by quartic phase aberration after transmission through a spherically aberrated lens is reported. The analysis shows that for a given beam size, the increase in the M2 parameter is less for a higher order transverse mode beam as compared to that for a diffraction limited beam. Experimental results using a multimode laser diode beam show good agreement with the theoretical results.