34 research outputs found
Enhanced light absorption in Tamm metasurface with a bound state in the continuum
We consider light absorption in a germanium grating placed on top of
photonic-crystalline substrate. Such a system supports an optical Tamm state
decoupled from the continuous spectrum with its frequency within the photonic
band gap. We have demonstrated that application of the Tamm state makes in
possible to engineer extremely narrow absorber which provides a 100% absorption
in a semiconductor grating in the critical coupling regime. The proposed design
may be used at both normal and oblique incidence at the telecom wavelength