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Updated: Apr 7, 2026
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Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
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Gate controlled resonant widths in double-bend waveguides: bound states in the continuum
Almas F Sadreev1, Dmitrii N Maksimov, Artem S Pilipchuk
1Kirensky Institute of Physics Siberian Branch of Russian Academy of Sciences, 660036, Krasnoyarsk, Russia.
Summary
Quantum transmission through shaped waveguides is analyzed using a non-Hermitian Hamiltonian approach. Chirality differences in Z and [Formula: see text] waveguides affect transmission, and gate potentials enable control over resonances and bound states in the continuum.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Nanophotonics
Background:
- Waveguides are crucial for controlling quantum particle flow.
- Understanding quantum transmission in complex geometries is essential for device applications.
- Resonances and bound states in the continuum (BICs) are key phenomena in quantum transport.
Purpose of the Study:
- To investigate quantum transmission through double-bend [Formula: see text]- and Z-shaped waveguides.
- To explain the origin of transmission resonances using the effective non-Hermitian Hamiltonian.
- To explore the influence of gate potential on waveguide transmission and BIC formation.
Main Methods:
- Utilized the effective non-Hermitian Hamiltonian approach.
- Analyzed quantum transmission through [Formula: see text]- and Z-shaped waveguide structures.
- Investigated the role of finger gate potential in controlling transmission properties.
Main Results:
- Explained transmission resonances via the non-Hermitian Hamiltonian.
- Observed distinct transmission characteristics in short [Formula: see text] and Z waveguides due to chirality.
- Demonstrated selective control over resonant widths and the emergence of bound states in the continuum.
Conclusions:
- The study provides insights into quantum transport in complex waveguide geometries.
- Chirality plays a significant role in differentiating transmission in [Formula: see text] and Z waveguides.
- Gate-controlled potentials offer a mechanism for manipulating quantum states, including BICs.
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