3,133 research outputs found
Purcell effect in wire metamaterials
We study theoretically the enhancement of spontaneous emission in wire
metamaterials. We analyze the dependence of the Purcell factor dependence on
wire dielectric constant for both electric and magnetic dipole sources, and
find an optimal value of the dielectric constant for maximizing the Purcell
factor for the electric dipole. We obtain analytical expressions for the
Purcell factor and also provide estimates for the Purcell factor in realistic
structures operating in both microwave and optical spectral range.Comment: 15 pages, 7 figure
Tailoring optical nonlinearities via the Purcell effect
We predict that the effective nonlinear optical susceptibility can be
tailored using the Purcell effect. While this is a general physical principle
that applies to a wide variety of nonlinearities, we specifically investigate
the Kerr nonlinearity. We show theoretically that using the Purcell effect for
frequencies close to an atomic resonance can substantially influence the
resultant Kerr nonlinearity for light of all (even highly detuned) frequencies.
For example, in realistic physical systems, enhancement of the Kerr coefficient
by one to two orders of magnitude could be achieved
Purcell effect in Hyperbolic Metamaterial Resonators
The radiation dynamics of optical emitters can be manipulated by properly
designed material structures providing high local density of photonic states, a
phenomenon often referred to as the Purcell effect. Plasmonic nanorod
metamaterials with hyperbolic dispersion of electromagnetic modes are believed
to deliver a significant Purcell enhancement with both broadband and
non-resonant nature. Here, we have investigated finite-size cavities formed by
nanorod metamaterials and shown that the main mechanism of the Purcell effect
in these hyperbolic resonators originates from the cavity hyperbolic modes,
which in a microscopic description stem from the interacting cylindrical
surface plasmon modes of the finite number of nanorods forming the cavity. It
is found that emitters polarized perpendicular to the nanorods exhibit strong
decay rate enhancement, which is predominantly influenced by the rod length. We
demonstrate that this enhancement originates from Fabry-Perot modes of the
metamaterial cavity. The Purcell factors, delivered by those cavity modes,
reach several hundred, which is 4-5 times larger than those emerging at the
epsilon near zero transition frequencies. The effect of enhancement is less
pronounced for dipoles, polarized along the rods. Furthermore, it was shown
that the Purcell factor delivered by Fabry-Perot modes follows the dimension
parameters of the array, while the decay rate in the epsilon near-zero regime
is almost insensitive to geometry. The presented analysis shows a possibility
to engineer emitter properties in the structured metamaterials, addressing
their microscopic structure
Measuring acceleration using the Purcell effect
We show that a two-level atom resonantly coupled to one of the modes of a
cavity field can be used as a sensitive tool to measure the proper acceleration
of a combined atom-cavity system. To achieve it we investigate the relation
between the transition probability of a two-level atom placed within an ideal
cavity and study how it is affected by the acceleration of the whole. We
indicate how to choose the position of the atom as well as its characteristic
frequency in order to maximize the sensitivity to acceleration.Comment: 5 pages, 5 figures, published versio
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