Doubly resonant single-layer bandpass optical filters.
A bandpass filter based on guided-mode resonance effects in a single-layer periodic waveguide is presented. Strong refractive-index modulation is used to support the excitation of a resonance pair in which leaky waveguide mode TE0 is excited by the second diffraction order and TE2 by the first diffraction order. It is shown that one resonance provides a broad low-transmission band, whereas the other supplies the transmission peak through its asymmetrical line shape. A bandpass filter with central wavelength at 1.55 microm is presented to demonstrate this concept.
Ding
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Y
Department of Electrical and Computer Engineering, University of Connecticut, Storrs, Connecticut 06268-1157, USA.
Magnusson
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R