Micro/nanoscale radiation transfer in whispering-gallery mode (WGM) microcavities is investigated. Each cavity consists of a waveguide and a microdisk coupled in a planar chip. In order to characterize the WGM resonance phenomena, studies of configuration parameters, specifically the microdisk size, the gap distance separating the microdisk and waveguide, and the waveguide width are numerically conducted. The finite element method is used for solving Maxwell’s equations which govern the propagation of electromagnetic (EM) field and the radiation energy transport in the micro/nanoscale WGM structures. The EM fields and the radiation energy distributions in the microcavities are then obtained. The scattering spectra for three different microdisk sizes are also obtained; and through which the WGM resonant properties such as the quality factor, the full-width at half maximum (FWHM), the free spectral range, and the finesse of the resonant modes are analyzed. It is found that the resonant frequencies and their free spectral ranges are predominantly determined by the size of the microcavity; while the FWHM, finesse, and quality factor are strong functions of the gap.

1.
H.M. Nussenzveig, Diffraction effects in semiclassical scattering, Cambridge University Press, New York (1992).
2.
P.W. Barber and P.K. Chang, Optical effects associated with small particles, World Scientific, Singapore; New Jersey; Hong Kong (1988).
3.
Gorodetsky
M. L.
,
Savchenkov
A. A.
, and
Ilchenko
V. S.
, “
Ultimate Q of optical microsphere resonators
,”
Opt. Lett.
,
21
,
453
455
(
1996
).
4.
Cai
M.
,
Painter
Q.
,
Vahala
K. J.
, and
Sercel
P. C.
, “
Fiber-coupled microsphere laser
,”
Opt. Lett.
,
25
,
1430
1432
(
2000
).
5.
Spillane
S. M.
,
Kippenberg
T. J.
, and
Vahala
K. J.
, “
Ultralow-threshold Raman laser using a spherical dielectric microcavity
,”
Nature
,
415
,
621
623
(
2002
).
6.
Schiller
S.
, and
Byer
R. L.
, “
High-resolution spectroscope of whispering gallery modes in large dielectric spheres
,”
Opt. Lett.
,
16
,
1138
1140
(
1991
).
7.
Vollmer
F.
,
Braun
D.
,
Libchaber
A.
,
Khoshsima
M.
,
Teraoka
I.
, and
Arnold
S.
, “
Protein detection by optical shift of a resonant microcavity
,”
Appl. Phys. Lett.
, Vol.
80
, No.
21
, pp.
4057
4059
(
2002
).
8.
Arnold
S.
,
Khoshsima
M.
,
Teraoka
I.
, and
Vollmer
F.
, “
Shift of whispering-gallery modes in microspheres by protein adsorption
,”
Opt. Lett.
,
28
,
272
274
(
2003
).
9.
Serpenguzel
A.
,
Arnold
S.
, and
Griffel
G.
, “
Excitation of resonances of microspheres on an optical fiber
,”
Opt. Lett.
,
20
,
654
656
(
1995
).
10.
Knight
J. C.
,
Cheung
G.
,
Jacques
F.
, and
Birks
T. A.
, “
Phase-matched excitation of whispering gallery mode resonances using a fiber taper
,”
Opt. Lett.
,
22
,
1129
1131
(
1997
).
11.
Little
B. E.
,
Chu
S. T.
,
Haus
H. A.
,
Foresi
J.
, and
Laine
J. P.
, “
Microring resonator channel dropping filters
,”
J. Lightwave Tech.
,
15
,
998
1005
(
1997
).
12.
Blom
F. C.
,
van Dijk
D. R.
,
Hoekstra
H. J
,
Driessen
A.
, and
Popma
T. J. A.
, “
Experimental study of integrated-optics micro-cavity resonators: toward an all-optical switching device
,”
Appl. Phys. Lett.
,
71
,
747
749
(
1997
).
13.
Levi
A. F. J.
,
Slusher
R. E.
,
McCall
S. L.
,
Glass
J. L.
,
Pearton
S. J.
, and
Logan
R. A.
, “
Directional light coupling from microdisk laser
,”
Appl. Phys. Lett.
,
62
,
561
563
(
1993
).
14.
Boyd
R. W.
, and
Heebner
J. E.
, “
Sensitive disk resonator photonic biosensor
,”
Appl. Opt.
,
40
,
5742
5747
(
2001
).
15.
Klunder
D. J. W.
,
Tan
F. S.
,
van der Veen
T.
,
Bulthuis
H. F.
,
Sengo
G.
,
Docter
B.
,
Hoekstra
H. J. W. M.
, and
Driessen
A.
, “
Experimental and numerical study of SiON microresonators with air and polymer cladding
,”
J. Lightwave Technol.
,
21
,
1099
1110
(
2003
).
16.
Blair
S.
and
Chen
Y.
, “
Resonant-enhanced evanescent-wave fluorescence biosensing with cylindrical optical cavities
,”
Appl. Opt.
,
40
,
570
582
(
2001
).
17.
Arnold
Teraoka S.
, and
Vollmer
F.
, “
Perturbation approach to resonance shifts of whispering-gallery modes in a dielectric microsphere as probe of a surrounding medium
,”
J. Opt. Soc. Am. B
,
20
,
1937
1946
(
2003
).
18.
Silvester
P. P.
, “
Finite element solution of homogeneous waveguide problems
,”
Alta Frequenza
,
38
,
313
317
(
1969
).
19.
Quan
H.
and
Guo
Z.
, “
Simulation of whispering-gallery-mode resonance shifts for optical miniature biosensors
,”
J. Quantitative Spectroscopy & Radiative Transfer
,
93
,
231
243
(
2005
).
20.
A. Yariv, Optical electronics in modern communications, 5th ed., Oxford U. Press, Oxford, UK (1997).
21.
A. Kovetz, The principles of electromagnetic theory, Cambridge University Press, New York (1990).
This content is only available via PDF.
You do not currently have access to this content.