范德华反铁磁体CrSBr基异质结构中自旋依赖层间杂化产生的大偏置可调磁电阻
Large bias-tunable magnetoresistance from spin-dependent interlayer hybridization in van der Waals antiferromagnet CrSBr-based heterostructures
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中文总结 AI 辅助
该研究在CrSBr基异质结构中实现20 K下350%的大磁电阻，揭示其源于自旋依赖层间杂化的磁构型依赖带边，排除Jullière模型等机制，为磁电阻调控提供新途径。
中文摘要 AI 辅助
我们研究了\boldsymbol{\text{hBN}}/少层石墨烯/\boldsymbol{\text{CrSBr}}/少层石墨烯异质结构中的大磁电阻（MR），并揭示其非单调偏置依赖的机制。以偏置电压和温度为独立调控旋钮，在20 K下实现了高达350%的MR，其特征为在±0.5 V附近呈对称的M形极大值。通过易轴磁场连续调控磁化角θ，发现势垒带边偏移与cos(θ/2)呈线性关系，这是自旋依赖层间杂化的一阶特征。该线性关系排除了Jullière模型和自旋过滤投影机制，我们得出结论：磁构型依赖的带边而非电极自旋极化，决定了\boldsymbol{\text{CrSBr}}结中的大磁电阻。
英文摘要
We explore the large magnetoresistance (MR) in \ce{hBN}/few-layer-graphene/\ce{CrSBr}/few-layer-graphene heterostructures and reveal the mechanism behind its non-monotonic bias dependence. Using bias voltage and temperature as independent tuning knobs, we achieve MR up to \SI{350}{\percent} at \SI{20}{K}, characterized by symmetric M-shaped maxima around $\pm 0.5\,\mathrm{V}$. Continuous tuning of the magnetization angle $θ$ via a hard-axis magnetic field shows that the barrier band-edge offset varies linearly with $\cos(θ/2)$, a first-order signature of spin-dependent interlayer hybridization. This linear relationship rules out the Jullière model and a spin-filter projection. We conclude that the magnetic-configuration-dependent band edge, rather than electrode spin polarization, dictates the large magnetoresistance in \ce{CrSBr} junctions.
