ELECTRON-TRANSPORT IN MESOSCOPIC GAAS/ALGAAS-STRUCTURES WITH SUPERCONDUCTING CONTACTS

被引：5

作者：

LENSSEN, KMH

WESTERLING, LA

JEEKEL, PCA

HARMANS, CJPM

MOOIJ, JE

LEYS, MR

VANDERVLEUTEN, W

WOLTER, JH

BEAUMONT, SP

机构：

[1] EINDHOVEN UNIV TECHNOL,5600 MB EINDHOVEN,NETHERLANDS

[2] UNIV GLASGOW,GLASGOW G12 8QQ,SCOTLAND

来源：

PHYSICA B | 1994年 / 194卷 / pt 2期

关键词：

Andreev reflection - Cooper pair - High electron mobility - Reflectionless tunneling - Superconducting contact - Superconducting properties - Two dimensional electron gas;

D O I：

10.1016/0921-4526(94)91706-X

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

For the first time an enhancement of weak localization by Andreev-reflection has been measured. This means that the interface between the Sn/Ti contacts and the two-dimensional electron gas (2DEG) in the GaAs/AlGaAs-heterostructure is practically barrier-free. The effect can be depressed by increased temperature, a DC bias current or a small magnetic field, but also by a voltage on a nearby gate. Also the sign of the temperature dependence of the differential resistance changes when the weak localization has disappeared. Further we report preliminary measurements on superconducting contacts to a shallow 2DEG. The transmission of this interface is probably not ver high, since there are indications for an excess conductance caused by reflectionless tunneling.

引用

页码：2413 / 2414

页数：2

共 8 条

[1]

Andreev A., 1966, ZH EKSP TEOR FIZ, V49, P455

[2]

ANDREEV AF, 1964, SOV PHYS JETP-USSR, V19, P1228

[3] QUANTUM TRANSPORT IN SEMICONDUCTOR-SUPERCONDUCTOR MICROJUNCTIONS [J].