Biomedical Engineering Reference
In-Depth Information
Figure 4.16
The radiative decay rate of the spontaneous emission of a
chiral molecule located in the gap of the two-sphere cluster in close vicinity
tothesurfaceofthefirstsphere(
1
r
0
→
a
,
2
r
0
=
l
−
a
)asthefunctionofthe
parameter
k
0
a
.(a)
0.1. The case
ofasingleparticlecorrespondstothemoleculeonthesurfaceofthesphere
(
r
0
→
ε
=
6,
μ
=
1,
χ
=
0; (b)
ε
=
6,
μ
=
1,
χ
=
a
).Thesolidlinecorrespondstothe“right”molecule(
m
0
=+
0.1
d
0
),
andthedashedlinecorrespondstothe“left”molecule(
m
0
=−
0.1
d
0
).Inthe
caseofnonchiralparticles,thedependenciesfor“right”and“left”molecules
coincide. The particles are placed in vacuum.
When the distance between the particles of the cluster is increased,
the difference remains, and the dependence of the spontaneous
emission radiative decay rate on
k
0
a
tends to the case of a single
particle.
Figure 4.17 shows the spontaneous radiative decay rate of chiral
molecules located near single chiral spherical particles (Fig. 4.17a)
and in the gap between chiral spherical particles of a cluster
(Fig.4.17b)asthefunctionsofchirality
χ
.Thefigureshowsthatthe
dependence of the radiative decay rate on the chirality parameter
can vary substantially in comparison with the dependence for a
single particle. It is well seen that the most significant difference
arises in the case of DNG-metamaterial particles. Indeed, in the case
of closely spaced DNG particles [
l
/
(2
a
)
=
1.1], there are a number
of high-
Q
resonances in the dependence of the radiative decay rate
on
χ
, and the dependence itself becomes rather complicated. In the
case of a cluster of two chiral dielectric particles, there is also a
substantialdifferencefromthecaseofasingleparticle.Inparticular,
it is seen that there is an increase of numbers of the radiative decay
maxima, but it is not as significant as in the case ofDNG particles.
