Open AccessTunable single-frequency lasing in a microresonator
Author(s) -
Simon J. Herr,
K. Buse,
Ingo Breunig
Publication year - 2019
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.015351
Subject(s) - lasing threshold , laser linewidth , laser , whispering gallery wave , optics , resonator , materials science , optoelectronics , whispering gallery , laser power scaling , free spectral range , wavelength , laser pumping , gain switching , physics
Whispering-gallery-mode resonators made of laser-active materials can serve as efficient microphotonic coherent light sources. However, the majority of experimental realizations relies on expensive pump light sources like narrow-linewidth or pulsed laser systems, which is inappropriate for most applications. In order to overcome this, we present a whispering-gallery laser system without the need for an expensive pump light source and at the same time with unprecedented laser performance: A laser-active resonator made of Nd:YVO 4 is non-resonantly excited, employing a low-cost laser diode without any external frequency stabilization, emitting up to 100 mW optical power around 810 nm wavelength. Continuous-wave single-frequency lasing at 1064 nm wavelength is achieved with directed laser light emission in the mW-regime. The temporal power and frequency stability are within ±1.5 % and ±30 MHz, respectively. Modehop-free frequency fine-tuning is achieved exceeding 11 GHz tuning range by changing the temperature of the cavity. Faster tuning can be expected when applying geometric or electro-optic instead of thermal tuning.