Robust realization of spin-polarized specular Andreev reflection in V$_2$O-based altermagnets

Yutaro Nagae; Andreas P. Schnyder; Satoshi Ikegaya

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arXiv · 2604.12695

Robust realization of spin-polarized specular Andreev reflection in V$_2$O-based altermagnets

Yutaro Nagae·Andreas P. Schnyder·Satoshi Ikegaya

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Abstract

We theoretically investigate charge transport in a junction between a conventional superconductor and a V$_2$O-based altermagnet exhibiting distinctive spin-split quasi-one-dimensional Fermi surfaces. The altermagnet is described by a microscopically motivated six-orbital model that incorporates sublattice degrees of freedom associated with both V and O sites. Based on calculations performed under various boundary conditions, we demonstrate the robust emergence of specular Andreev reflection with a distinctive spin polarization. Furthermore, we propose an efficient multiterminal setup to detect this specular Andreev reflection through nonlocal conductance measurements. Our results establish V$_2$O-based altermagnets as a promising platform for realizing spin-resolved Cooper pair splitting, which is essential for generating energy-entangled electron pairs.

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Yutaro Nagae, Andreas P. Schnyder, Satoshi Ikegaya. 2026-04-14. Robust realization of spin-polarized specular Andreev reflection in V$_2$O-based altermagnets. https://arxiv.org/abs/2604.12695

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