Superconductor/Semiconductor Junctions (Springer Tracts in Modern Physics)

✍ Scribed by Thomas Schäpers

• Publisher: Springer
• Year: 2001
• Tongue: English
• Leaves: 132
• Series: Springer Tracts in Modern Physics
• Edition: 1
• Category: Library

✦ Synopsis

This book describes superconductor/two-dimensional-electron-gas (2DEG) structures with the aim of providing a better understanding of their transport properties. The two-dimensional electron gas used for the structures described here is buried either in a III-V semiconductor heterostructure or in an inversion layer at the surface. First, the properties of a single superconductor/2DEG structure are discussed on the basis of Andreev reflection and the proximity effect. Then, the properties of superconductor/2DEG Josephson junctions are treated. The last part of the book discusses the control of junctions using gate electrodes or injection currents, and the physical effects observed in these junctions.

✦ Table of Contents

1. Introduction......Page 1
   2.1 The Bogoliubov Equation......Page 4
   2.2.1 Andreev Reflection......Page 7
   2.2.2 Blonder–Tinkham–Klapwijk Model......Page 8
   2.2.3 Inclusion of the Proximity Effect......Page 13
   3.1.1 Two-Dimensional Electron Gases in Inversion Layers......Page 19
   3.1.2 Two-Dimensional Electron Gases in Heterostructures......Page 22
   3.2 Fabrication of Superconductor/Two-Dimensional-Electron-Gas/Superconductor Junctions......Page 24
   3.2.1 Junctions Based on a Surface Inversion Layer......Page 25
   3.2.2 Junctions Based ona Buried Two-Dimensional Electron Gas......Page 26
   4.1.1 Preparation of Single S/2DEG Contacts......Page 29
   4.1.2 Samples Cleaned by Wet Chemical Etching......Page 31
   4.1.3 Ar+ Sputter Cleaning......Page 34
   4.1.4 Electron Cyclotron Resonance Plasma Cleaning......Page 39
   4.2 Point Contact Spectroscopy......Page 41
   5.1.1 K¨ummel–Gunsenheimer–Nicolsky Model......Page 45
   5.1.2 Inclusion of Normal Reflection at the SN Interface......Page 47
   5.1.3 Octavio–Tinkham–Blonder–Klapwijk Model......Page 49
   5.1.4 Inclusion of the Proximity Effect......Page 51
   5.2.1 Andreev Current in S/2DEG/S Structures......Page 54
   5.2.2 Subharmonic Gap Structures......Page 55
   5.2.3 Subharmonic Gap Structures and the Proximity Effect......Page 58
   5.3 Resonant Structures and Interference Effects......Page 59
   6.1 Theoretical Description of the Supercurrentin an S/2DEG/S Junction......Page 63
   6.1.1 Supercurrent in an Ideal One-Dimensional SNS Junction......Page 64
   6.1.2 Supercurrentin a General One-Dimensional SNS Junction......Page 66
   6.1.3 Supercurrent in a Junctionwitha Two-Dimensional Electron Gas......Page 73
   6.1.4 Supercurrent in a Junction withPro ximity Layers......Page 74
   6.2 Measurements of the Superconductive State......Page 75
   6.2.1 Current–Voltage Characteristics......Page 76
   6.2.2 Effect of a Magnetic Field......Page 81
   6.2.3 Hysteresis......Page 84
   6.2.4 Self-Detection of Josephson Radiation......Page 86
   6.2.5 Light Exposure......Page 87
   7.1 The Josephson Field Effect Transistor......Page 93
   7.2.1 Critical-Current Oscillations......Page 98
   7.2.2 Mesoscopic Fluctuations and Localization Effects......Page 100
   7.3 Superconducting Quantum Point Contacts......Page 103
   8.1 Supercurrent Control by Nonequilibrium Carriers:Theoretical Concepts......Page 109
   8.1.1 Carrier Injection in a Three-Terminal Structure......Page 110
   8.1.2 Carrier Injection in a Four-Terminal Junction......Page 115
   8.2.1 Carrier Injection in an InAs Step Junction......Page 119
   8.2.2 Multiterminal Josephson Junctions......Page 121
   8.2.3 Local Suppression of the Josephson Current......Page 128
   9. Conclusion......Page 131