Wavelength tunability of laser based on Yb-doped GGAG crystal

Abstract

The wavelength tunability of a diode-pumped laser, based on Yb 3+ -doped mixed garnet Gd 3 Ga 5−x Al x O 12 (Yb:GGAG, x ≈ 2.2, 4.25% Yb/Gd, 2.7 mm thick) crystal was investigated. Absorption and emission spectra together with fluorescence decay time were measured. The longitudinally diode-pumped Yb:GGAG laser was continuously tuned over ∼47 nm (from 1019 nm up to 1066 nm). The maximum output power amplitude of 1.6 W was obtained at wavelength 1042 nm with an absorbed pump power amplitude 6.9 W. The corresponding tunable laser slope efficiency was 30%.

Diode-pumped laser and spectroscopic properties of Yb,Ho:GGAG at 2 µm and 3 µm

“…It has to be noted that because of the ratio between the fluorescence decay times at the upper 5 I 6 (309 µs) and lower 5 I 7 (7.8 ms) energy levels, the Yb,Ho:GGAG can suffer from a self-termination (bottleneck) effect at the ∼3 µm transition, similarly to erbium-doped active media [4,11]. It is also interesting to compare the measured decay time of Yb 3+ ( 2 F 5/2 level) in the GGAG crystal with (190 µs) and without Ho 3+ (917 µs) codoping [14], which proves the efficiency of the Yb 3+ → Ho 3+ energy transfer. Diode-pumped Yb,Ho:GGAG laser; pumping mirror (PM)-HT @ 971 nm, HR @ 2.0-2.2 µm or 2.65-2.95 µm, output coupler (OC)-R = 97% @ 2.0-2.2 µm or R = 99% @ 2.65-2.95 µm both with r OC = 150 mm, BF-birefringent MgF 2 plate 2 mm thick.…”

Development and prospects of garnet ceramic scintillators: A review

“…However, it also provides a new way of thinking to delve into the specificity of the multicomponent garnets. It is worth mentioning that in addition to the application in the scintillators, it is also easier for the multicomponent garnet to achieve ultrashort pulse lasers with wavelength tunability due to the wider emission band [220][221][222][223]. Moreover, due to the higher brightness and tunable luminescence, the multicomponent garnets can also be prepared into phosphors and ceramics for high-power white LEDs by introducing different luminescent centers [224,225].…”

Tunable resonantly pumped Er:GGAG laser

“…Er:YSGG [12]. The multi-site structure of mixed garnets results in broadband absorption and emission, preserving good thermal conductivity [13][14][15][16]. The wider emission line makes it possible to tune the emitted laser wavelength.…”