Large tunneling magnetoresistance in all-altermagnetic tunnel junctions · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title
Large tunneling magnetoresistance in all-altermagnetic tunnel junctions
Plain
Theory predicts that a tunnel junction made only of altermagnets should change its resistance strongly when one electrode's spin pattern is reversed, giving a memory bit without ferromagnets. No experiment has yet shown this in a junction built only from altermagnets.
Precise · changed · core
Revision 1: In an altermagnet/insulator/altermagnet junction (candidates CrSb, Cr-doped RuO2, KV2Se2O, MnTe) with no ferromagnetic layer, measure $\mathrm{TMR}=(R_{\mathrm{AP}}-R_{\mathrm{P}})/R_{\mathrm{P}}$ at $T=300\,\mathrm{K}$, where P and AP denote parallel and antiparallel Neel vectors, and determine whether it exceeds 100 percent as nonrelativistic spin-splitting theory predicts. An answer is the measured TMR with device structure and evidence that it arises from the altermagnetic band splitting.
Revision 2: In an altermagnet/insulator/altermagnet junction (candidates CrSb, Cr-doped $\mathrm{RuO_2}$, $\mathrm{KV_2Se_2O}$, MnTe) with no ferromagnetic layer, measure $\mathrm{TMR}=(R_{\mathrm{AP}}-R_{\mathrm{P}})/R_{\mathrm{P}}$ at $T=300\,\mathrm{K}$, where P and AP denote parallel and antiparallel Neel vectors, and determine whether it exceeds 100 percent as nonrelativistic spin-splitting theory predicts. An answer is the measured TMR with device structure and evidence that it arises from the altermagnetic band splitting.
Settled by
Epitaxial all-altermagnet junctions with controlled Neel-vector switching and room-temperature TMR measurements.
Kind
well-posed
Answer type
value
References
(empty)
Literature status
open
Status note · changed
Revision 1: Work found for 2025-2026 is theoretical: a CrSb-based junction proposal (arXiv:2503.13850) and a first-principles all-altermagnet Cr-doped RuO2/TiO2/Cr-doped RuO2 junction (arXiv:2607.21092); no experimental all-altermagnet junction with TMR above 100 percent at 300 K was found.
Revision 2: Work found for 2025-2026 is theoretical: a CrSb-based junction proposal (arXiv:2503.13850) and a first-principles all-altermagnet Cr-doped $\mathrm{RuO_2}$/$\mathrm{TiO_2}$/Cr-doped $\mathrm{RuO_2}$ junction (arXiv:2607.21092); no experimental all-altermagnet junction with TMR above 100 percent at 300 K was found.
Posed since
2022

Decisions