title: Generation of a cylindrically symmetric, polarized laser beam with narrow linewidth and fine tunability.
abstract: We demonstrated a generation of cylindrically symmetric, polarized laser beams with narrow linewidth and fine tunability. Since an LP11 mode beam in an optical fiber is a superposition of an HE21 (hybrid) mode beam and a TE01 or TM01 mode beam, firstly, a higher order transverse (TEM01 or TEM10) mode laser beam with narrow linewidth and fine tunability was generated from an external cavity diode laser (ECDL) in conjunction with a phase adjustment plate. Then the beam generated was passed in a two mode optical fiber. A doughnut shaped laser beam with the cylindrically symmetric polarization (a radially or azimuthally polarized beam) was obtained by properly adding stress-induced birefringence in the optical fiber.
authors.forename: Toru
authors.initials: T
authors.lastname: Hirayama
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kozawa
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakamura
authors.forename: Shunichi
authors.initials: S
authors.lastname: Sato