Low-threshold microlaser in a high-Q asymmetrical microcavity.
We experimentally report an asymmetrical spherical microcavity with thermal-induced deformation, in which five-bounce whispering-gallery modes possess not only ultrahigh quality factors (Q) but also remarkably directional escape emission from the microsphere boundary. With efficient free-space excitation and collection, a low-threshold microlaser is demonstrated and exhibits a highly directional emission. Our measurement agrees well with the theoretical predictions by corrected Fresnel law.
Xiao
Y-F
YF
Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China.
Dong
C-H
CH
Zou
C-L
CL
Han
Z-F
ZF
Yang
L
L
Guo
G-C
GC