On-chip green silica upconversion microlaser.
We demonstrate an erbium-doped silica toroidal microcavity upconversion laser on a silicon chip lasing in the visible spectral range (510-580 nm). The microcavity is pumped at 1458 nm by a tapered optical fiber coupled to the cavity and the lasing threshold is 690 muW. Lasing is observed at room temperature despite the high nonradiative relaxation rates of Er in pure silica that usually precludes upconversion lasing from higher excited states. This is attributed to the very high circulating pump power in the high-Q microcavity (Q>10(7)).
Lu
Tao
T
Applied Physics Department, California Institute of Technology, Pasadena, California 91125, USA.
Yang
Lan
L
van Loon
Rob V A
RV
Polman
Albert
A
Vahala
Kerry J
KJ