Superconductor/Semiconductor Junctions

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