Spin-dependent transient current in transistor-like nanostructures
Spin-dependent transient current in transistor-like nanostructures
复制标题
类晶体管纳米结构中的自旋相关瞬态电流
DOI：
10.1088/1361-648x/aba292
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
and H. Ishida
中科院分区：
文献类型：
--
作者：
K. Asano;T. Sako;and H. Ishida
用一维有效势中的几个电子模型研究了晶体管类纳米结构中的暂态电流，该一维有效势由源极、栅极和漏极三个量子阱组成。借助于辛积分法对电子的含时薛定谔方程进行了积分，并用位于漏极区远边缘的复数吸收势吸收电子的几率密度的通量来计算暂态电流。对于给定的自旋多重数，电子最初被放置在源域中作为其最低能态，并且针对不同的栅势高计算了源漏电流。不同自旋组态的电流在不同的栅势下表现出很强的发射，这表明可以利用所研究的纳米结构从自旋未极化的正常电流中提取具有特定自旋组态的电流。通过改变源区的大小，研究了电流发射与电子关联的关系。在中等和强限制条件下，不同自旋组态的电流显示出明显的差异，而这些差异在较小的限制条件下变得较小，并且在较弱的限制条件下趋于减小。这种观察到的趋势在维格纳晶格态形成的基础上得到了合理的解释。
Transient current in transistor-like nanostructures has been studied by a model of a few electrons confined in a one-dimensional effective potential consisting of three quantum wells,'source','gate', and'drain'. The time-dependent Schrödinger equation for the electrons has been integrated relying on the symplectic integrator method and the transient current has been calculated as the flux of the probability density of electrons absorbed by the complex absorbing potential placed at the far edge of the drain region. The electrons are initially placed in the source domain as their lowest-energy state for a given spin multiplicity and the source–drain current has been calculated for different gate potential heights. The current for different spin configurations has shown strong emission at different values of the gate potential, suggesting use of the studied nanostructures for extracting current with a specific spin configuration from spin-unpolarized normal current. Dependence of the current emission on electron correlation has also been studied by changing the size of the source domain. The current has shown appreciable differences for different spin configurations for the medium and strong confinement regimes, while these differences become smaller for smaller confinement and tend to diminish in the weak limit of confinement. This observed trend has been rationalized on the basis of the formation of the Wigner lattice states.