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arXiv · 2611.04396

Dissipationless valley diode effects in Kekulé graphene superlattices

W. Zeng
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Abstract

Superconducting diodes have attracted considerable interest for nonreciprocal device applications owing to their dissipationless transport. Here, we theoretically propose that a tunnel junction based on the Kekulé graphene superlattice can host a finite valley supercurrent that exhibits pronounced nonreciprocity even in the absence of superconductivity, giving rise to a dissipationless valley diode effect. This effect originates from the additional reflection phase acquired by electrons in each transverse channel and supports perfect valley diode rectification with $100\%$ efficiency, which can be readily tuned via the gate voltage. This finding provides a platform for designing dissipationless valleytronics in a more versatile manner.

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W. Zeng. 2026-11-03. Dissipationless valley diode effects in Kekulé graphene superlattices. https://arxiv.org/abs/2611.04396

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