Manganese telluride calculations yield three resistance states
A theoretical study identified three distinguishable resistance states in a proposed magnetic junction using alpha manganese telluride. The calculations show that electrode choice and the atomic structure of interfaces change electron transport through the material. The result points to a possible route for multistate memory research, while fabrication and device performance remain experimental challenges.
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Magnetic order changes electron transport
A peer-reviewed theoretical study in npj Spintronics examined alpha manganese telluride, a material in the altermagnet class. Its compensated magnetic order can coexist with electronic structures that depend on spin, an intrinsic electron property. The researchers modeled magnetic interactions and electron transport. Their calculated magnetic order regenerated basic features previously established experimentally, before they investigated the material in a proposed junction.[1]
The proposed junction has three resistance states
They placed manganese telluride in the calculations between a pair of magnetic electrodes as a thin intervening barrier. Electrons tunnel through this barrier, with transport depending on the magnetic arrangement of the electrodes and the intervening material. Appropriately selected electrodes yielded three distinguishable resistance states. Those states are relevant to research on memory designs encoding information in distinct values of electrical resistance.[1]
Electrodes and interfaces constrain the design
Cobalt electrodes did not provide the desired improvement in spin selectivity. Layered electrodes containing iron, germanium and tellurium matched the barrier better, while the atoms at the interface also changed calculated transport. The study fabricated no working multistate memory. Clean ultrathin interfaces, retained magnetic order and usable resistance contrasts remain practical challenges, alongside approximations in the theoretical treatment of transport.[1]
