Generalized Energy Band Alignment Model for van der Waals Heterostructures with a Charge Spillage Dipole.

Lee, Seungjun; Lee, Eng Hock; Kwon, Young-Kyun; Koester, Steven J; Avouris, Phaedon; Cherkassky, Vladimir; Tersoff, Jerry; Low, Tony · ACS Nano · 2025

basic_science · Level V

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Abstract

The energy band alignment at the interface of van der Waals heterostructures (vdWHs) is a key design parameter for next-generation electronic and optoelectronic devices. Although the Anderson and midgap models have been widely adopted for bulk semiconductor heterostructures, they exhibit severe limitations when applied to vdWHs, particularly for type-III systems. Based on first-principles calculations for approximately 10<sup>3</sup> vdWHs, we demonstrate that these traditional models miss a critical dipole arising from interlayer charge spillage. We introduce a generalized linear response (gLR) model that includes this dipole through a quantum capacitance term while remaining analytically compact. With only two readily computed inputs, the charge neutrality level offset and the sum of the isolated-layer bandgaps, the gLR reproduces density functional theory (DFT) band line-ups with <i>r</i><sup>2</sup> ∼ 0.9 across type-I, -II, and -III stacks. Machine learning feature analysis confirms that these two descriptors dominate the underlying physics, indicating that the model is near-minimal and broadly transferable. The gLR framework therefore provides both mechanistic insight and a fast and accurate surrogate for high-throughput screening of the vast vdW heterostructure design space.