Magnetocapacitance of quantum wires: Effect of confining potential on one-dimensional subbands and suppression of exchange enhanced g factor
Magnetocapacitance of quantum wires: Effect of confining potential on one-dimensional subbands and suppression of exchange enhanced g factor
复制标题
量子线的磁电容：限制势对一维子带的影响和交换增强 g 因子的抑制
DOI：
10.1103/physrevb.65.125303
复制
发表时间：
2002
影响因子：
3.7
通讯作者：
W. Hansen
中科院分区：
文献类型：
--
作者：
I. Pallecchi;C. Heyn;J. Lohse;B. Kramer;W. Hansen
利用磁电容测量方法，研究了场效应诱导GaAs/AlGaAs异质结量子线阵列的子带填充。限制电位是由叉形叉指金属栅极光刻宽度为150 nm，实现了电子束光刻。电容使我们能够研究态密度。分析并定量解释了一维子带间距和填充随约束、栅电压和磁场的变化规律。还研究了与自旋分裂有关的结构的发展作为磁场和约束的函数。在不同的制度，我们发现的g因子的增强到几乎50倍的“裸”值或抑制，占交换相互作用和动能的边缘电子，分别与理论模型一致。
By means of magnetocapacitance measurements, we study subband filling in field effect induced arrays of quantum wires in GaAs/AlGaAs heterostructures. The confining potential is defined by fork-shaped interdigitated metallic gates with lithographic width of ∼150 nm, realized by e-beam lithography. The capacitance allows us to investigate the density of states. Evolution of one-dimensional subband spacing and filling as a function of confinement, gate voltage and magnetic field is analyzed and quantitatively explained. Also the development of a structure related to spin splitting is studied as a function of both magnetic field and confinement. In different regimes, we find for the g factor either an enhancement up to a factor of almost 50 with respect to the "bare" value or a suppression, accounting for exchange interactions and kinetic energy of edge electrons, respectively, in agreement with theoretical models.