All-fiber Q-switched single-frequency Tm-doped laser near 2 μm

Abstract

We present an all-fiber Q-switched single-frequency laser oscillator operating in the eye-safe region at 1950 nm. It is based on the stress-induced polarization modulation in a Tm-doped distributed Bragg reflector fiber laser. The laser emits Q-switched single-frequency laser pulses with a pulse repetition rate ranging from tens of hertz to hundreds of kilohertz and an average power of several milliwatts. Pulse duration and laser spectral linewidth have been characterized. This is, to our best knowledge, the first demonstration of a Q-switched single-frequency fiber laser near 2 microm.

Mid-Infrared Lasers

“…A number of single-frequency Tm fiber lasers and amplifiers were demonstrated, including a 1.95-m CW laser with less than 3-kHz linewidth [29], a 1950-nm Q-switched laser [30], a tunable, 0.3-nm linewidth laser that operated from 1.981 to 2.095 m [31], and a 20-W, 100-kHz-linewidth, polarization-maintaining amplifier [32]. Additionally, a picosecond-class mode-locked laser was demonstrated using a fiber less than 1 m in length [33], and a 750-fs Tm:fiber laser was mode locked using a carbon nanotube saturable absorber [34].…”

Mid-infrared emission properties and energy transfer evaluation in Tm3+ doped fluorophosphate glasses

“…Moreover, a 3 dB power flatness of 200 nm with a maximum output power of 30 mW at 1.93 μm was determined [7]. In addition, all-fiber Q-switched single-frequency Tm-doped laser near 2 μm was also reported [8].…”

Single-tuning dual-pulse Er^3+-doped Q-switched all-fiber laser

“…The high Q-factor is realized when the reflective peaks of two FBGs is coincident, and the Q-switched laser pulses up to 530 mW peak powers at 3 kHz are obtained with 2~3 μs temporal widths [1]. Similarly using the PZT element, by transverse stress-induced polarization modulation in a Tmdoped distributed Bragg reflector, a Q-switched Tm-doped fiber laser is reported which a several Watts peak power and several hundred nanosecond of pulse duration [2]. In 2005, P. Pérez-Millán using the magnetostrictive element replace PZT element, Q-switched pulses of more than 1 W peak power Er 3+ -doped fiber laser is obtained, with a pulse repetition rate varying from 1 Hz to 125 kHz [3].…”