Volume Bragg Grating assisted broadband tunability and spectral narrowing of Ti:Sapphire oscillators

Abstract

A widely tunable, narrow band Ti:Sapphire oscillator is reported. Tunability and spectral narrowing were achieved by use of a volume Bragg grating in the cavity. Tunability was observed from 785 nm to 852 nm while maintaining a spectral linewidth less than 10 pm with essentially no spectral jitter. Oscillation on only 2 longitudinal modes is also reported at 852 nm with the grating at normal incidence providing approximately 200 mW output power.

Sub-5-pm linewidth, 130-nm-tuning of a coupled-cavity Ti:sapphire oscillator via volume Bragg grating-based feedback

“…In particular, the VBG is utilized to provide external feedback to tune and stabilize the center lasing wavelength of a Ti:sapphire oscillator while narrowing the spectral width is ensured by the coupled-cavity architecture. Using such technique, we present a tuning range spanning from 714 to 842 nm, representing a two-fold improvement from previously reported work involving an intracavity VBG [15,18]. In our approach, the spectral linewidth is kept below 5 pm over the entire tuning range with an output power reaching several hundred milliwatts.…”

“…Previous works have shown that when used as an intra-cavity turning mirror VBGs act as both a narrowing and a wavelength tuning element. Tuning ranges as wide as 50 nm have been reported for a Yb:KYW oscillator [14] and up to 65 nm for a Ti:sapphire oscillator while keeping a spectral linewidths less than 10 pm [15].…”

Highly efficient resonantly pumped 2000 nm Tm:YAG ceramic laser

“…A maximum pump power of 4.56 W with a bandwidth full width at half maximum (FWHM) of <0.5 nm was available. 20,21 The plane OC were coated with transmittance of 5%, 10% and 20% at 2000-2250 nm and with high reflectivity (>97%) at the pump light. 15 Schematic diagram of the Tm:YAG ceramic laser setup was illustrated in Fig.…”

High-Performance Solid-State and Fiber Lasers Controlled by Volume Bragg Gratings

“…The use of PTR Bragg mirrors for solid state lasers enabled spectral narrowing down to couple picometers with approximately the same power as for a laser with a conventional output coupler. 18,19,20 This means that spectral brightness of those lasers was increased by three orders. It is important that even for fiber lasers with large length of resonators and, therefore, small distance between longitudinal modes, it was possible to make an external resonator with a VBG output coupler and to observe single frequency operation.…”