title: Mid-infrared rotated image singly resonant twisted rectangle optical parametric oscillator based on HgGa(2)S(4) pumped at 1064 nm.
abstract: We compare linear, planar ring, and rotated image singly resonant twisted rectangle (RISTRA) type nanosecond optical parametric oscillator cavities using HgGa2S4nonlinear crystal pumped by 8 ns pulses at 1064 nm from a low beam quality pump source. The input-output characteristics and the output idler beam quality at 6300 nm are compared for two values of the pump beam diameter presenting different cavity Fresnel numbers and magnitudes of the spatial walk-off effect due to birefringence. The RISTRA cavity ensures in all cases a circular output beam profile but is advantageous in terms of beam quality with respect to the planar ring only at a large pump beam diameter.
authors.forename: Georgi
authors.initials: G
authors.lastname: Marchev
authors.forename: Manuel
authors.initials: M
authors.lastname: Reza
authors.forename: Valeriy
authors.initials: V
authors.lastname: Badikov
authors.forename: Adolfo
authors.initials: A
authors.lastname: Esteban-Martin
authors.forename: Georg
authors.initials: G
authors.lastname: Stöppler
authors.forename: Marina
authors.initials: M
authors.lastname: Starikova
authors.forename: Dmitrii
authors.initials: D
authors.lastname: Badikov
authors.forename: Vladimir
authors.initials: V
authors.lastname: Panyutin
authors.forename: Marc
authors.initials: M
authors.lastname: Eichhorn
authors.forename: Galina
authors.initials: G
authors.lastname: Shevyrdyaeva
authors.forename: Aleksey
authors.initials: A
authors.lastname: Tyazhev
authors.forename: Svetlana
authors.initials: S
authors.lastname: Sheina
authors.forename: Antonio
authors.initials: A
authors.lastname: Agnesi
authors.forename: Anna
authors.initials: A
authors.lastname: Fintisova
authors.forename: Valentin
authors.initials: V
authors.lastname: Petrov