Characterization of Superconducting Single-Electron Transistors with Small Al/AlOx/V Josephson Junctions
Characterization of Superconducting Single-Electron Transistors with Small Al/AlOx/V Josephson Junctions
复制标题
具有小型 Al/AlOx/V 约瑟夫森结的超导单电子晶体管的表征
DOI：
10.1088/0953-2048/27/11/115015
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发表时间：
2014
影响因子：
3.6
通讯作者：
and Y. Mizugaki
中科院分区：
文献类型：
--
作者：
H. Shimada;K. Miyawaki;A. Hagiwara;K. Takeda;and Y. Mizugaki
制备了由Al/AlOx/V小结组成的超导单电子晶体管，并研究了其输运特性。具有Al岛的器件在栅电荷中呈现2e周期的超电流，而具有V岛的器件具有e的周期性，其中e是基本电荷。在ΔΔ+<；<；+E e VE||3 Al c Al c范围内，约瑟夫森准粒子(Jqp)循环电流出现在偏置电压V处，其中ΔAl是Al的超导带隙，EC是基元电荷的充电能.这与通常接受的JQP电流范围不同，例如在全铝SSET的情况下。在ΔΔΔ⩽<；+e VE2||2()Al V Alc处也出现了较大的漏电流，其中ΔV是V的超导带隙，所有这些特性都是通过考虑V电极中有限的子能隙准粒子密度来解释的。
Superconducting single-electron transistors (SSETs) composed of small Al/AlOx/V junctions were fabricated, and their transport properties were investigated. The device with an Al island exhibited a supercurrent that was 2e-periodic in the gate charge while that with a V island showed a periodicity of e, where e is an elementary charge. The Josephson-quasiparticle (JQP)-cycle current appeared at the bias voltage V in the range Δ Δ+<<+ E e V E|| 3 Al c Al c, where ΔAl is the superconducting gap of Al and Ec is the charging energy of an elementary charge. This is different from the commonly accepted range for the JQP current such as that in the case of an all Al SSET. There also appeared a large leakage current at Δ Δ Δ⩽<++ e V E 2|| 2 () Al V Al c, where ΔV is the superconducting gap of V. All these properties are accounted for by considering the finite subgap quasiparticle density of states in the V electrode.