97-μJ single frequency linearly polarized nanosecond pulsed laser at 775 nm using frequency doubling of a high-energy fiber laser system

Guoqing Zhou,Jinhui Li,Liang Qi,Qiang Fang,Wei Shi,Xuelong Cui,Zhuo Zhang

doi:10.1117/1.oe.56.8.086112

Abstract

We report a high-energy (∼97 μJ), high-peak power (∼20 kW), single-frequency, linearly polarized, near diffraction-limited (M2<1.2) ∼4.8-ns pulsed laser source at 775 nm with a 260-Hz repetition rate. This laser was achieved by frequency doubling of a high-energy linearly polarized all-fiber-based master oscillator–power amplifier, seeded by a single-frequency semiconductor distributed feedback laser diode at 1550 nm. The frequency doubling is implemented in a single-pass configuration using a periodically poled lithium niobate crystal, and a conversion efficiency of 51.3% was achieved.

Highlights

Rare-earth-doped glass fiber lasers have seen progressive developments in the past two decades in various aspects, such as high power, high energy, ultrashort pulse width, narrow linewidth, etc.[1,2] Fiber lasers can only operate in certain spectra range, such as 1,3 1.5,4 2,5 or 2.8 μm,[6] due to the limit of the emission spectra for the rare-earth-elements doped in glasses
The frequency doubling of narrow linewidth Er-doped fiber lasers can generate narrow linewidth laser sources around 780 nm, which can be utilized for optical atom cooling, quantum information storage, etc
Thompson et al.[11] demonstrated a single-frequency continuous wave (CW) 780-nm laser source with 900-mW laser power, generated from the frequency doubling of a fiber laser system using the cascaded periodically poled lithium niobate (PPLN) crystals

Summary

Introduction

Rare-earth-doped glass fiber lasers have seen progressive developments in the past two decades in various aspects, such as high power, high energy, ultrashort pulse width, narrow linewidth (single frequency), etc.[1,2] Fiber lasers can only operate in certain spectra range, such as 1,3 1.5,4 2,5 or 2.8 μm,[6] due to the limit of the emission spectra for the rare-earth-elements doped in glasses. Champert et al.[18] demonstrated a nanosecond pulsed laser at 772 nm by frequency doubling of a distributed feedback (DFB) laser diode seeded ytterbium–erbium fiber amplifier in a periodically poled KTP crystal. We report a single-frequency, linearly polarized, near diffraction-limited, pulsed laser source at 775 nm by frequency doubling a single-frequency nanosecond pulsed all-fiber-based master oscillator–power amplifier (MOPA) and seeded by a fiber coupled semiconductor DFB laser diode at 1550 nm. This 775-nm laser can provide ∼4.8-ns single-frequency laser pulses with a 260-Hz repetition rate, ∼97-μJ pulse energy, and ∼20-kW peak power

Low Repetition Rate High-Energy Fiber Laser System

Generation of the High-Energy Single-Frequency Laser Pulses at 775 nm

Conclusion