Continuously tunable pulsed Ti:Sa laser self-seeded by an extended grating cavity

TL;DR

This paper presents a novel self-seeded Ti:Sa laser with an extended grating cavity that achieves continuous tunability, higher power, and narrow linewidth by coupling two oscillators within a modified cavity design.

Contribution

It introduces a simple cavity modification that enhances power and tunability of Ti:Sa lasers by coupling broadband and narrowband oscillators within a single cavity.

Findings

Significantly increased laser output power.

Maintained narrow linewidth despite power enhancement.

Enabled higher pump power without grating thermal issues.

Abstract

A continuously tunable titanium:sapphire (Ti:Sa) laser self-seeded by an extended grating cavity was demonstrated and characterized. By inserting a partially reflecting mirror inside the cavity of a classic single-cavity grating laser, two oscillators are created: a broadband power oscillator, and a narrowband oscillator with a prism beam expander and a diffraction grating in Littrow configuration. By coupling the grating cavity oscillation into the power oscillator, a power-enhanced narrow-linewidth laser oscillation is achieved. Compared to the classic grating laser, this simple modification significantly increases the laser output power without considerably broadening the linewidth. With most of the oscillating laser power confined inside the broadband power cavity and lower power incident onto the grating, the new configuration also allows higher pump power, which is typically limited by the thermal deformation of the grating coating at high oscillation power.