In this work, we demonstrate that the compound mode properties of coupled photonic-crystal cavities can depend
critically on the interplay of distance between cavities and their longitudinal shifts. Thus the robust control over the
cavity modes can be imposed. The simple coupled-mode theory employed for such systems predicts a peculiar behavior
of band dispersion in the slow light regime at the photonic band-edge. In particular, it reveals an interesting effect that
the frequency detuning of the fundamental supermodes in the coupled cavities can be reduced down to zero. We
anticipate that this property will be generic for side-coupled cavity systems irrespectively of the individual cavity design,
e.g. point-defect cavities in a photonic crystal or linear cavities in one-dimensional arrays of elements (rods or holes).
We report here about the finite-difference frequency-domain method (FDFD) developed by us to analyze nanocavities
with a very high Q-factor. The method is utilized to confirm by simulations the coupled-mode theory predictions. As an
example we choose coupled cavities in one-dimensional periodic arrays of holes in dielectric nanowires known also as
nanobeams.
As an alternative to adaptive-grid finite-element analysis, the full-vector finite-difference computations of a Bragg
fiber are performed on a polar grid "stretched" radially to better resolve the multilayer cladding of the fiber.
We analyze theoretically the modal dispersion of N-period planar waveguides with a bilayer unit cell containing thin magnetized metal film. Three basic configurations of external dc magnetic field are discussed: transversal, polar, and longitudinal. On the basis of coordinate-free surface-impedance formalism we derive compact analytical formula for the characteristic transmission matrix of the magnetized layer in case of polar configuration, which is to our knowledge the novel and non-trivial result. We show that increasing the number of periods leads to prohibition of qTE mode guidance, but find it unrealistic to tailor the band structure of the system by magnetizing the metal films. Alternatively, we propose to control polarization states of the guided modes through magnetization.
For a bilayered, N-period, photonic band gap (PBG) structure produced of anisotropic and isotropic layers, we derive analytic expressions for the tensorial density of modes (DOM) and optical transmittance of the structure as a whole. The computations of the DOM-tensor for different physically realizable PBG structures prove the possibility of considerable enhancement of one normal electromagnetic mode and simultaneous depression of the other one. This effect, which is called polarization selection of modes in anisotropic one-dimensional PBG crystals, enables us to design an effective plane-stratified polarizer working in near-optical frequency range, totally reflecting one normal mode and transmitting the other.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.