Barium fluoride whispering-gallery-mode disk-resonator with one billion quality-factor

Abstract

We demonstrate a monolithic optical whispering gallery mode resonator fabricated with barium fluoride (BaF${}_2$) with an ultra-high quality ($Q$) factor above $10^9$ at $1550$ nm, and measured with both the linewidth and cavity-ring-down methods. Vertical scanning optical profilometry shows that the root mean square surface roughness of $2$ nm is achieved for our mm-size disk. To the best of our knowledge, we show for the first time that one billion $Q$-factor is achievable by precision polishing in relatively soft crystals with mohs hardness of ~$3$. We show that complex thermo-optical dynamics can take place in these resonators. Beside usual applications in nonlinear optics and microwave photonics, high energy particle scintillation detection utilizing monolithic BaF${}_2$ resonators potentially becomes feasible.

References in corpus (2)

• Optical combs with a crystalline whispering gallery mode resonator
• Brillouin Lasing with a CaF_2 Whispering Gallery Mode Resonator

Cited by in corpus (3)

• Optimization of laser stabilization via self-injection locking to WGM microresonator
• Cascaded Brillouin lasing in monolithic barium fluoride whispering gallery mode resonators
• On the dispersion management of fluorite whispering-gallery mode resonators for Kerr optical frequency comb generation in the telecom and mid-infrared range