Micro/nanoscale radiation energy transfer is investigated in optical microcavity and waveguide coupling structures working on whispering-gallery mode optical resonances. The finite element method is employed for solving the Helmholtz equations that govern the energy transfer and time-harmonics electromagnetic (EM) wave propagation. The maximum element size concept is introduced for the numerically sensitive subdomains where local mesh refining is needed because of the presence of intensified EM fields. The results show that the energy storage capability of a resonant microcavity is predominantly determined by the cavity size. The stored energy in the 10μm diameter microcavity considered is several orders of magnitude larger than that in the 2μm diameter microcavity. The gap between a microcavity and its light-delivery waveguide has a substantial effect on the energy coupling from the waveguide to the microcavity and consequently influences significantly energy storage in the microcavity. An optimal gap is found for maximum energy storage and most efficient energy coupling. This optimal gap dimension depends not only on the configurations of the microcavity and waveguide, but also on the resonance wavelength. With increasing gap the quality factor increases exponentially and quickly saturates as the gap approaches to one wavelength involved. The submicron/nanoscale gap is crucial for generating quality resonances as well as for efficient energy transfer and coupling.

1.
Hill
,
S. C.
, and
Benner
,
R. E.
, 1988, “
Morphology-Dependent Resonances
,” in
Optical Effects Associated with Small Particles
,
P. W.
Barber
and
P. K.
Chang
, eds.,
World Scientific
,
Singapore
, pp.
3
61
.
2.
Arnold
,
S.
, 2001, “
Microspheres, Photonic Atoms and the Physics of Nothing
,”
Am. Sci.
0003-0996,
89
(
5
), pp.
414
421
.
3.
Collot
,
L.
,
Lefèvre-Seguin
,
V.
,
Brune
,
M.
,
Raimond
,
J. M.
, and
Haroche
,
S.
, 1993, “
Very High-Q Whispering Gallery Modes Resonances Observed on Fused Silica Microspheres
,”
Europhys. Lett.
0295-5075,
23
(
5
), pp.
327
333
.
4.
Gorodetsky
,
M. L.
,
Savchenkov
,
A. A.
, and
Ilchenko
,
V. S.
, 1996, “
Ultimate Q of Optical Microsphere Resonators
,”
Opt. Lett.
0146-9592,
21
(
7
), pp.
453
455
.
5.
Vahala
,
K. J.
, 2003, “
Optical Microcavities
,”
Nature (London)
0028-0836,
424
(
6950
), pp.
839
846
.
6.
Mabuchi
,
H.
, and
Doherty
,
A. C.
, 2002, “
Cavity Quantum Electrodynamics: Coherence in Context
,”
Science
0036-8075,
298
(
5597
), pp.
1372
1377
.
7.
Cai
,
M.
,
Painter
,
Q.
,
Vahala
,
K. J.
, and
Sercel
,
P. C.
, 2000, “
Fiber-Coupled Microsphere Laser
,”
Opt. Lett.
0146-9592,
25
(
19
), pp.
1430
1432
.
8.
Blom
,
F. C.
,
van Dijk
,
D. R.
,
Hoekstra
,
H. J.
,
Driessen
,
A.
, and
Popma
,
T. J. A.
, 1997, “
Experimental Study of Integrated-Optics Micro-Cavity Resonators: Toward an All-Optical Switching Device
,”
Appl. Phys. Lett.
0003-6951,
71
(
6
), pp.
747
749
.
9.
Little
,
B. E.
,
Chu
,
S. T.
,
Haus
,
H. A.
,
Foresi
,
J.
, and
Laine
,
J. P.
, 1997, “
Microring Resonator Channel Dropping Filters
,”
J. Lightwave Technol.
0733-8724,
15
(
6
), pp.
998
1005
.
10.
Krioukov
,
E.
,
Klunder
,
D. J. W.
,
Driessen
,
A.
,
Greve
,
J.
, and
Otto
,
C.
, 2002, “
Integrated Optical Microcavities for Enhanced Evanescent-Wave Spectroscopy
,”
Opt. Lett.
0146-9592,
27
(
17
), pp.
1504
1506
.
11.
Vollmer
,
F.
,
Braun
,
D.
,
Libchaber
,
A.
,
Khoshsima
,
M.
,
Teraoka
,
I.
, and
Arnold
,
S.
, 2002, “
Protein Detection by Optical Shift of a Resonant Microcavity
,”
Appl. Phys. Lett.
0003-6951,
80
(
21
), pp.
4057
4059
.
12.
Quan
,
H.
, and
Guo
,
Z.
, 2005, “
Simulation of Whispering-Gallery-Mode Resonance Shifts for Optical Miniature Biosensors
,”
J. Quant. Spectrosc. Radiat. Transf.
0022-4073,
93
(
1–3
), pp.
231
243
.
13.
Dubreuil
,
N.
,
Knight
,
J. C.
,
Leventhal
,
D. K.
,
Sandoghdar
,
V.
,
Hare
,
J.
, and
Lefèvre
,
V.
, 1995, “
Eroded Monomode Optical Fiber for Whispering-Gallery Mode Excitation in Fused-Silica Microspheres
,”
Opt. Lett.
0146-9592,
20
(
8
), pp.
813
815
.
14.
Gorodetsky
,
M. L.
, and
Ilchenko
,
V. S.
, 1999, “
Optical Microsphere Resonators: Optimal Coupling to High-Q Whispering-Gallery Modes
,”
J. Opt. Soc. Am. B
0740-3224,
16
(
1
), pp.
147
154
.
15.
Serpenguzel
,
A.
,
Arnold
,
S.
, and
Griffel
,
G.
, 1995, “
Excitation of Resonances of Microspheres on an Optical Fiber
,”
Opt. Lett.
0146-9592,
20
(
4
), pp.
654
656
.
16.
Knight
,
J. C.
,
Cheung
,
G.
,
Jacques
,
F.
, and
Birks
,
T. A.
, 1997, “
Phase-Matched Excitation of Whispering Gallery Mode Resonances Using a Fiber Taper
,”
Opt. Lett.
0146-9592,
22
(
15
), pp.
1129
1131
.
17.
Klunder
,
D. J. W.
,
Krioukov
,
E.
,
Tan
,
F. S.
,
van Der Veen
,
T.
,
Bulthuis
,
H. F.
,
Sengo
,
G.
,
Otto
,
C.
,
Hoekstra
,
H. J. W. M.
, and
Driessen
,
A.
, 2001, “
Vertically and Laterally Waveguide-Coupled Cylindrical Microresonators in Si3N4 on SiO2 Technology
,”
Appl. Phys. B
0946-2171,
73
(
5–6
), pp.
603
608
.
18.
Guo
,
Z.
,
Quan
,
H.
, and
Pau
,
S.
, 2005, “
Optical Resonance in Fabricated Whispering-Gallery Mode Microcavity
,”
ASME J. Heat Transfer
0022-1481,
127
(
8
), p.
808
.
19.
Arnold
,
S.
, 2005, private communications, Polytechnic University, Brooklyn, NY.
20.
Siegel
,
R.
, and
Howell
,
J. R.
, 2001,
Thermal Radiation Heat Transfer
,
4th ed.
,
Taylor & Francis
,
New York
.
21.
Modest
,
M. F.
, 2003,
Radiative Heat Transfer
,
2nd ed.
,
Academic Press
,
New York
.
22.
Kumar
,
S.
, 1994, “
Thermal Radiation Transport in Micro-Structures
,”
Therm. Sci. Eng.
0918-9963,
2
(
2
), pp.
149
157
.
23.
Tien
,
C. L.
,
Qiu
,
T. Q.
, and
Norris
,
P. M.
, 1994, “
Microscale Thermal Phenomena in Contemporary Technology
,”
Therm. Sci. Eng.
0918-9963,
2
(
1
), pp.
1
11
.
24.
Chen
,
G.
, 1996, “
Heat Transfer in Micro- and Nanoscale Photonic Devices
,” in
Annual Review of Heat Transfer
,
C. L.
Tien
, ed.,
CRC
,
Boca Raton, FL
, Vol.
VII
, pp.
1
57
.
25.
Longtin
,
J. P.
, and
Tien
,
C. L.
, 1997, “
Microscale Radiation Phenomena
,” in
Miscroscale Energy Transfer
,
C. L.
Tien
,
A.
Majumdar
, and
F. M.
Gerner
, eds.,
Taylor and Francis
,
Washington, DC
, pp.
119
147
.
26.
Jackson
,
J. D.
, 1998,
Classical Electrodynamics
,
3rd ed.
,
Wiley
,
New York
.
27.
Chen
,
G.
, 1997, “
Wave Effects on Radiative Transfer in Absorbing and Emitting Thin-Film Media
,”
Microscale Thermophys. Eng.
1089-3954,
1
(
3
), pp.
215
224
.
28.
Majumdar
,
A.
, 2004, “
Thermoelectricity in Semiconductor Nanostructures
,”
Science
0036-8075,
303
(
5659
), pp.
777
778
.
29.
Grigoropoulos
,
C. P.
, 1994, “
Heat Transfer in Laser Processing of Thin Films
,”
Annual Review of Heat Transfer
, Vol.
V
,
C. L.
Tien
, ed.,
CRC
,
Boca Raton, FL
, pp.
77
130
.
30.
Chen
,
S. C.
,
Cahill
,
D. G.
, and
Grigoropoulos
,
C. P.
, 2000, “
Melting and Surface Deformation in Pulsed Laser Surface Micro-Modification of NiP Disks
,”
ASME J. Heat Transfer
0022-1481,
122
(
1
), pp.
107
112
.
31.
Taflove
,
A.
, and
Hagness
,
S. C.
, 2000,
Computational Electrodynamics: The Finite-Difference Time-Domain Method
,
2nd ed.
,
Artech House
,
Norwood, MA
.
32.
Guo
,
Z.
,
Quan
,
H.
, and
Pau
,
S.
, 2006, “
Numerical Characterization of Whispering-Gallery Mode Optical Microcavities
,”
Appl. Opt.
0003-6935,
45
(
4
), pp.
611
618
.
You do not currently have access to this content.