title: Diode-pumped 2 μm vibronic (Tm3+, Yb3+):KLu(WO4)2 laser.
abstract: We report on laser operation in a (6 at. % Tm, 5 at. % Yb):KLu(WO4)2 codoped crystal. The vibrational frequencies of KLu(WO4)2 are coupled to the electronic transitions of Tm3+ at 1946 nm, creating virtual final laser levels at higher energy than the ground level 3H6 of Tm3+. The longest recorded laser wavelength was 2039 nm, which is longer than permitted by a pure electronic transition in Tm3+ ions in KLu(WO4)2. We show that every laser wavelength can be explained with the electron-phonon coupling effect, where the vibration frequencies were determined through Raman spectroscopy.
authors.affiliation: Física i Cristallografía de Materials i Nanomaterials (FiCMA-FiCNA-EMAS), Universitat Rovira i Virgili (URV), Carrer de Marcellí Domingo s/n, Tarragona, Spain.
authors.forename: Martha
authors.initials: M
authors.lastname: Segura
authors.forename: Xavier
authors.initials: X
authors.lastname: Mateos
authors.forename: Maria Cinta
authors.initials: MC
authors.lastname: Pujol
authors.forename: Joan Josep
authors.initials: JJ
authors.lastname: Carvajal
authors.forename: Magdalena
authors.initials: M
authors.lastname: Aguiló
authors.forename: Francesc
authors.initials: F
authors.lastname: Díaz
authors.forename: Uwe
authors.initials: U
authors.lastname: Griebner
authors.forename: Valentin
authors.initials: V
authors.lastname: Petrov
mesh_terms: D053844:Lasers, Solid-State; D055096:Optical Devices; D055620:Optical Phenomena; D013059:Spectrum Analysis, Raman; D013932:Thulium; D017973:Tungsten Compounds; D015019:Yttrium
chemical_list: D017973:Tungsten Compounds; D015019:Yttrium; D013932:Thulium; C045951:tungstate