We demonstrate the generation of a radially polarized beam by simply inserting an undoped c-cut YVO4 crystal into a Nd:YAG laser cavity. In a hemispherical cavity, the cylindrically symmetric, positive birefringence of the YVO4 crystal extends the stability limit of the cavity length for an extraordinary ray (radial polarization) compared to an ordinary one (azimuthal polarization). By adjusting the cavity length, a radially polarized beam with an output power up to 1 W was selectively obtained. In addition, a higher-order transverse mode was also generated by arranging the cavity design. The method demonstrated in this paper can be readily applied to laser systems with an isotropic laser medium.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Physics and Astronomy (miscellaneous)