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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
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Identical band gaps in structurally re-entrant honeycombs.
1Department of Engineering Mechanics, Northwestern Polytechnical University, Xi'an 710072, People's Republic of China.
The Journal of the Acoustical Society of America
|September 3, 2016
Summary
Structurally re-entrant honeycombs exhibit identical band gaps in different configurations due to folded sheet resonance. This finding aids in designing lattice metamaterials for elastic wave control.
Area of Science:
- Materials Science
- Acoustics
- Mechanical Engineering
Background:
- Structurally re-entrant honeycombs are artificial lattice materials with unique star-like unit cells and high connectivity.
- These materials feature re-entrant topology and at least six folded sheets joined at each vertex.
Purpose of the Study:
- To investigate in-plane elastic wave propagation in highly connected re-entrant honeycombs.
- To explore the band characteristics of structurally square re-entrant honeycomb (SSRH) and structurally hexagonal re-entrant honeycomb (SHRH).
Main Methods:
- Finite element method (FEM) combined with Bloch's theorem was employed.
- Analysis focused on two distinct lattice configurations: SSRH and SHRH.
Main Results:
- Identical band gaps, in terms of location and width, were observed in both SSRH and SHRH configurations.
- The presence of identical band gaps is attributed to the resonance of the folded sheets within the unit cells.
- Heuristic models were developed to explain the underlying physics of these identical band gaps.
Conclusions:
- The phenomenon of identical band gaps in re-entrant honeycombs is significant for understanding lattice material behavior.
- Structurally re-entrant honeycombs serve as promising host structures for developing metamaterials for elastic wave control.
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