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Published on: December 1, 2023
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Multi-dimensional band structure spectroscopy in the synthetic frequency dimension.
Dali Cheng1, Eran Lustig1, Kai Wang1,2
1Ginzton Laboratory and Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA.
Light, Science & Applications
|June 27, 2023
Summary
Researchers developed a new method to measure multi-dimensional band structures in photonic synthetic dimensions. This technique fully characterizes high-dimensional physics in synthetic lattices, advancing topological photonics research.
Area of Science:
- Photonics
- Condensed Matter Physics
- Quantum Physics
Background:
- Synthetic dimensions in photonics enable exploration of multi-dimensional physics.
- Band structure characterization is crucial for understanding these phenomena.
- Current methods are limited to one-dimensional Brillouin zones in synthetic frequency dimensions.
Purpose of the Study:
- To theoretically propose and experimentally demonstrate a method for fully measuring multi-dimensional band structures in the synthetic frequency dimension.
- To overcome limitations of existing one-dimensional Brillouin zone measurements.
- To enable comprehensive characterization of high-dimensional physics in photonic synthetic lattices.
Main Methods:
- Utilizing a single photonic resonator under dynamical modulation to create a multi-dimensional synthetic frequency lattice.
- Introducing a gauge potential into the lattice Hamiltonian to enable full Brillouin zone band structure measurement.
- Experimental measurement of two-dimensional band structures for both Hermitian and non-Hermitian Hamiltonians.
Main Results:
- Successful demonstration of a method to fully measure multi-dimensional band structures in the synthetic frequency dimension.
- Experimental measurement of 2D band structures for Hermitian and non-Hermitian Hamiltonians.
- Observation of general properties of point-gap topology in a multi-dimensional non-Hermitian Hamiltonian.
Conclusions:
- The proposed method provides a complete way to measure multi-dimensional band structures in photonic synthetic dimensions.
- This technique allows for the full characterization of high-dimensional physical phenomena.
- The findings pave the way for exploring complex topological properties in synthetic systems.
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