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Interface problems have wide applications in modern scientific research. Obtaining accurate numerical solutions of multi-domain problems involving triple junction conditions remains a significant challenge. In this paper, we develop an efficient finite element method based on non-body-fitting meshes for solving multi-domain elliptic interface problems. We follow the idea of immersed finite element by modifying local basis functions to accommodate interface conditions. We enrich the local finite element space by adding new basis functions for handling non-homogeneous flux jump. The numerical scheme is symmetric and positive definite. Numerical experiments are provided to demonstrate the features of our method.
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Efficient Modeling of Electron Transport with Plane Waves
We present a method to simulate ballistic quantum transport in one-dimensional nanostructures, such as extremely scaled transistors, with a channel of nanowires or nanoribbons. In contrast to most popular approaches, we develop our method employing an accurate plane-wave basis at the atomic scale while retaining the numerical efficiency of a localized (tight-binding) basis at larger scales. At the core of our method is a finite-element expansion, where the finite element basis is enriched by a set of Bloch waves at high-symmetry points in the Brillouin zone of the crystal. We demonstrate the accuracy and efficiency of our method with the self-consistent simulation of ballistic transport in graphene nanoribbon FETs.
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- Award ID(s):
- 1710066
- PAR ID:
- 10101170
- Date Published:
- Journal Name:
- Efficient Modeling of Electron Transport with Plane Waves
- Page Range / eLocation ID:
- 71 to 74
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/SISPAD.2018.8551730
