1,186 research outputs found
Measurement of the linear thermo-optical coefficient of GaInP using photonic crystal nanocavities
GaInP is a promising candidate for thermally tunable
nanophotonic devices due to its low thermal conductivity. In this work we study
its thermo-optical response. We obtain the linear thermo-optical coefficient
by investigating the transmission
properties of a single mode-gap photonic crystal nanocavity.Comment: 7 pages, 4 figure
Oscillatory dynamics in nanocavities with noninstantaneous Kerr response
We investigate the impact of a finite response time of Kerr nonlinearities
over the onset of spontaneous oscillations (self-pulsing) occurring in a
nanocavity. The complete characterization of the underlying Hopf bifurcation in
the full parameter space allows us to show the existence of a critical value of
the response time and to envisage different regimes of competition with
bistability. The transition from a stable oscillatory state to chaos is found
to occur only in cavities which are detuned far off-resonance, which turns out
to be mutually exclusive with the region where the cavity can operate as a
bistable switch
Tuning out disorder-induced localization in nanophotonic cavity arrays
Weakly coupled high-Q nanophotonic cavities are building blocks of slow-light
waveguides and other nanophotonic devices. Their functionality critically
depends on tuning as resonance frequencies should stay within the bandwidth of
the device. Unavoidable disorder leads to random frequency shifts which cause
localization of the light in single cavities. We present a new method to finely
tune individual resonances of light in a system of coupled nanocavities. We use
holographic laser-induced heating and address thermal crosstalk between
nanocavities using a response matrix approach. As a main result we observe a
simultaneous anticrossing of 3 nanophotonic resonances, which were initially
split by disorder.Comment: 11 page
Dispersion of coupled mode-gap cavities
The dispersion of a CROW made of photonic crystal mode-gap cavities is
pronouncedly asymmetric. This asymmetry cannot be explained by the standard
tight binding model. We show that the fundamental cause of the asymmetric
dispersion is the fact that the cavity mode profile itself is dispersive, i.e.,
the mode wave function depends on the driving frequency, not the
eigenfrequency. This occurs because the photonic crystal cavity resonances do
not form a complete set. By taking into account the dispersive mode profile, we
formulate a mode coupling model that accurately describes the asymmetric
dispersion without introducing any new free parameters.Comment: 4 pages, 4 figure
Interplay of plasma-induced and fast thermal nonlinearities in a GaAs-based photonic crystal nanocavity
We investigate the nonlinear response of GaAs-based photonic crystal cavities
at time scales which are much faster than the typical thermal relaxation rate
in photonic devices. We demonstrate a strong interplay between thermal and
carrier induced nonlinear effects. We have introduced a dynamical model
entailing two thermal relaxation constants which is in very good agreement with
experiments. These results will be very important for Photonic Crystal-based
nonlinear devices intended to deal with practical high repetition rate optical
signals.Comment: 10 pages, 8 figures, Phys Rev A (accepted
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