Electron interference oscillations and spin-density-wave energy gaps at the Fermi surface of antiferromagnetic chromium
Electron interference oscillations and spin-density-wave energy gaps at the Fermi surface of antiferromagnetic chromium
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反铁磁铬费米表面的电子干涉振荡和自旋密度波能隙
DOI：
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发表时间：
1980
期刊：
影响因子：
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通讯作者：
E. Fawcett
中科院分区：
文献类型：
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作者：
R. Reifenberger;F. Holroyd;E. Fawcett
一个包含不相称自旋密度波周期性的链模型被用来描述反铁磁铬的费米表面，并且发现它与其他研究者获得的许多de Haas-van Alphen数据有很好的半定量一致性。本文提出了新的实验数据，证实了反铁磁铬中自旋密度波矢量Q∥[001]、电流J∥[010]和磁场H在（010）面[100]附近观测到的横向磁阻振荡的异常特征。在链模型的帮助下，这些异常特征被解释为电荷沿开放轨道沿q方向输运的量子干涉效应引起的。我们从实验数据中获得了表征干涉仪轨迹的磁击穿场的大小，以及与自旋密度波相关的费米表面上的能量间隙的估计。先前通过微扰计算得到的一个紧密结合的s电子模型的磁击穿场的理论估计与我们的值不太一致。
A chain model incorporating the periodicity of the incommensurate spin density wave is used to describe the Fermi surface of antiferromagnetic chromium, and is found to give excellent semiquantitative agreement with much of the de Haas-van Alphen data obtained by other investigators. New experimental data are presented which confirm the anomalous features of the transverse magnetoresistance oscillations observed in antiferromagnetic chromium with the spin density wave vector Q∥[001], the current J∥[010], and the magnetic field H in the (010) plane near [100]. These anomalous features are explained with the help of the chain model as arising from a quantum interference effect in the transport of charge along open orbits in the direction of Q. Estimates are obtained from our experimental data for the size of the magnetic breakdown fields that characterize the interferometer trajectories, and hence for the energy gaps on the Fermi surface associated with the spin density wave. Previous theoretical estimates of the magnetic breakdown fields obtained by a perturbation calculation for a model of tight-binding s electrons are in poor agreement with our values.