Critical tunneling currents in quantum Hall superfluids: Pseudospin-transfer torque theory
Critical tunneling currents in quantum Hall superfluids: Pseudospin-transfer torque theory
复制标题
量子霍尔超流体中的临界隧道电流：伪自旋传递力矩理论
DOI：
10.1103/physrevb.81.184523
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发表时间：
2010
影响因子：
3.7
通讯作者：
A. Macdonald
中科院分区：
文献类型：
--
作者：
Jung;A. Macdonald
在总填充因子$\nu=1$量子霍尔双层可以有一个自发的层间相位相干有序的基态。有序状态的实验信号显着增强层间隧道电导在低偏置电压，在较大的偏置电压层间电流是类似的无序状态。我们将这种行为的变化与临界电流的存在相关联，超过该临界电流，静态层间相位差不能保持，并研究该临界电流对样品几何形状，相位刚度和相干隧穿能量密度的依赖性。我们的分析部分是基于金属铁磁体中的相干双层行为和自旋转移矩物理之间的类比。与最近的实验比较表明，无序可以显着抑制临界电流。
At total filling factor $\nu=1$ quantum Hall bilayers can have an ordered ground state with spontaneous interlayer phase coherence. The ordered state is signaled experimentally by dramatically enhanced interlayer tunnel conductances at low bias voltages; at larger bias voltages inter-layer currents are similar to those of the disordered state. We associate this change in behavior with the existence of a critical current beyond which static inter-layer phase differences cannot be maintained, and examine the dependence of this critical current on sample geometry, phase stiffness, and the coherent tunneling energy density. Our analysis is based in part on analogies between coherent bilayer behavior and spin-transfer torque physics in metallic ferromagnets. Comparison with recent experiments suggests that disorder can dramatically suppress critical currents.