半导体泵浦Yb: Lu2Si2O7可调谐激光器

Abstract

Diode-pumped laser action of a new crystal Yb 3+ :Lu2Si2O7 (LPS) is demonstrated for the first time to our knowledge. An output power of 2.22 W at 1070 nm and a slope efficiency of 34.7% were achieved with a 5 at.-% Yb: LPS sample. The tuning can cover the range form 1034 to 1080 nm.OCIS codes: 140.3480, 140.3600, 140.3615. doi: 10.3788/COL20090711.1028.Recently, a variety of interesting results have been reported for continuous-wave (CW) or mode-locked operations based on the diode pumped Yb 3+ -doped materials [1−9] . However, a drawback of current Yb 3+ lasers is that Yb 3+ can only be operated in a quasi three-level scheme. Thermal populating of the terminal laser level causes strong re-absorption at the emission wavelengths, resulting in high laser pumping threshold power. In order to limit thermal population of the terminal level, a relatively strong crystal-field is expected. Thus, a low-symmetry crystal structure and multi-type of substitution sites are essential for ytterbium-doped host materials.Lutetium pyrosilicate crystal Lu 2 Si 2 O 7 (LPS) is a well known pyrosilicate that has been studied as a host for Ce 3+ ion with applications as phosphors and excellent scintillators [10−12] . But to the best of our knowledge, up to now laser action and CW tunable laser performance have never been reported for Yb:LPS crystals.Ytterbium-doped lutetium oxyorthosilicates Yb:Lu 2 -SiO 5 (Yb:LSO) single crystal is technologically important as a laser host material. More than 2.6-W average output with pulse durations of 260 fs at 1059 nm for Yb:LSO has been obtained [13] . Compared with Yb:LSO crystals, the advantages of Yb:LPS are the presence of effective low-symmetry monoclinic structure and its single crystallographic site, which are benefit for the low threshold and high output energy [14,15] . In this letter, we report, for the first time to our knowledge, the experimental investigation of laser diode (LD)-pumped CW and tunable Yb:LPS lasers. The output power reached 2.22 W at 1070 nm and the wavelength could be tuned from 1034 to 1080 nm.The 5×5×3 (mm) 5 at.-% Yb:LPS sample, provided by the R&D Center for Laser and Opto-Electronic Materials of Shanghai Institute of Optics and Fine Mechanics (SIOM) was grown by the Czochralski method from an inductively heated iridium crucible. Pure SiO 2, Lu 2 O 3 , and Yb 2 O 3 powders were mixed and pressed (200 MPa) into tablets. Nitrogen with purity of 5N was used as growth atmosphere. Finally, a colorless Yb:LPS crystal boule with a size up to 30 mm in length and diameter was obtained.The room-temperature absorption and fluorescence spectrum of the Yb:LPS crystal is shown in Fig. 1. The orientation of the sample used for test is (0 0 1) plane and the Yb 3+ concentration is 2.168×10 20 atom/cm 3 . We can observe that the absorption spectrum is mainly composed of three strong bands around 908, 976, and 1032 nm. Apparently, the absorption peak around 976 nm belongs to the zero-line transition between the lowest levels of 2 F 7/2 and 2 F 5/2 manifolds. The absorption coeff...

Diode-pumped femtosecond passively mode-locked Yb:LPS laser

“…The slope efficiencies with respect to the incident pump power were up to 70% and 53%, respectively, which indicated the good laser performance of Yb:LPS. Compared to 35% slope efficiency with respect to the absorbed pump power of Yb:LPS laser reported in [21], the laser performance was greatly enhanced in this work. The high efficiency is mainly contributed to the good mode match- ing in the crystal.…”

“…The broad absorption bandwidth of the Yb:LPS crystal is beneficial for the direct diode pumping. However, up to now except continuous wave (CW) operation [21] no mode locking of the crystal is investigated. In this letter we report on the passive modelocking operation of a diode pumped Yb:LPS laser.…”

Growth, spectral properties, and laser demonstration of Nd:(Lu0.5Gd0.5)2SiO5 crystal

“…Recently, silicate crystals have attracted more and more interest due to the low symmetry, high quantum efficiency, and excellent luminescence properties [13][14][15][16][17]. Lutetium gadolinium oxyorthosilicate ((Lu x Gd 1−x ) 2 SiO 5 , 0 < x < 1) was discovered in 1993 [18] as single crystal scintillator.…”