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arXiv · 2402.08600

Bipolar electron waveguides in two-dimensional materials with tilted Dirac cones

R. R. Hartmann·M. E. Portnoi
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Abstract

We show that the (2+1)-dimensional massless Dirac equation, which includes a tilt term, can be reduced to the biconfluent Heun equation for a broad range of scalar confining potentials, including the well-known Morse potential. Applying these solutions, we investigate a bipolar electron waveguide in 8-$Pmmn$ borophene, formed by a well and barrier, both described by the Morse potential. We demonstrate that the ability of two-dimensional materials with tilted Dirac cones to localize electrons in both a barrier and a well can be harnessed to create pseudogaps in their electronic spectrum. These pseudogaps can be tuned through varying the applied top-gate voltage. Potential opto-valleytronic and terahertz applications are discussed.

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R. R. Hartmann, M. E. Portnoi. 2024-02-13. Bipolar electron waveguides in two-dimensional materials with tilted Dirac cones. https://arxiv.org/abs/2402.08600

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