Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermo-Optical Tuning of Whispering Gallery Modes in Er:Yb Doped Glass
  Microspheres to Arbitrary Probe Wavelengths   We present experimental results on an all-optical, thermally-assisted
technique for broad range tuning of microsphere cavity resonance modes to
arbitrary probe wavelengths. An Er:Yb co-doped phosphate glass (Schott IOG-2)
microsphere is pumped at 978 nm via the supporting stem and the heat generated
by absorption of the pump light expands the cavity and changes the refractive
index. This is a robust tuning method that decouples the pump from the probe
and allows fine tuning of the microsphere's whispering gallery modes.
Pump/probe experiments were performed to demonstrate thermo-optical tuning to
specific probe wavelengths, including the 5S1/2 F = 3 to 5P3/2 F' = 4 laser
cooling transition of 85Rb. This is of particular interest for cavity QED-type
experiments, while the broad tuning range achievable is useful for integrated
photonic devices, including sensors and modulators.

29
The categories of this paper are: funct-an
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn