Prof. Dr. Dominik Zumbühl

**time and location of course: every Wednesday, 10:15am-12pm, Room 4.1**, Institute of Physics, Klingelbergstrasse 82.

organization of lecture

schedule and content

projects and presentations

literature

weekly lectures wednesdays 10:15am-12pm, Room 4.1, Institute of Physics.

syllabus 2D electron gas, quantum point contacts, quantum dots, conductance fluctuations, quantum phase coherence, Coulomb blockade, Kondo effect, few electron dots, spin blockade, spin relaxation, charge sensing, single spin measurement, spin manipulation and coherence, nuclear spins, electron spin resonance, spin qubits, quantum computation.

for: 6. semester bachelor and masters students in nanoscience and physics. physics III lecture is a prerequisite

2 credit points this lecture is a two hours per week course, no problem sets, final presentation, pass/fail.

purpose of this lecture is to bring the audience up to date on current experimental research in the field of quantum transport through nanostructures, focusing mainly on quantum dots in GaAs, spin-quibts in coupled dots and quantum computation. The lecture will inevitably discuss some simple condensed matter theory but **will mainly focus on experiments**

structure will be a combination of lectures on my part to intruduce the basics and subsequent presentations done by students towards the end of the semester on topics that can be chosen by students from a selection. There will be no problem sets, but moderate amounts of reading as preparation for lectures will be assigned. The class is pass/fail, and the evaluation will be based on the presentation given by each student taking the class for credit. Sit-ins/students auditing the class (not for credit) **are welcome**

date | lecture content | |
---|---|---|

oct 25 , wed, 10am | preliminary meeting | |

nov 1, wed, 10:15am | solid state physics backgroundcrystals, bands, effective mass approximation, spin-orbit coupling, GaAs conduction and valence bands, density of states, occupation of bands, intrinsic carrier concentration, semiconductor doping | |

nov 8, wed | no class | |

nov 15, wed, 10:15am | semiconductor surfaces and interfacessurface states, semiconductor-vacuum interface, band bending, Fermi level pinning, Schottky barrier and diodelecture notes pdf | |

nov 22, wed, 10:15am | 2D electron gases (GaAs)properties of 2DEGs, scattering mechanisms in 2DEGs and bulk GaAs, screening in 2D and 3D, Friedel Oscillations, ohmic contacts to 2DEGs, lateral gating and nanoscale deviceslecture notes pdf | |

nov 29, wed, 10:15am | experimental techniquessample fabrication, low temperature methods (chapter 4, Heinzel), quantum point contacts van Wees et al., PRL 60, 848 (1988) pdfvan Wees et al., PRB 38, 3625 (1988) pdf | |

dec 6, wed, 10:15am | concepts in mesoscopic physics IDrude conductivity, Einstein relation, mesoscopic time and length scales, classical Hall effect, (integer) quantum Hall effect | |

dec 13, wed, 10:15am | concepts in mesoscopic physics IIclassical Hall effect, (integer) quantum Hall effect, 1D subbands, quantum point contacts, 0.7 structure Cronenwett et al., PRL 88, 226805 (2002) pdf(lecture notes chapter 3: pdf) | |

dec 20, wed, 10:15am | quantum dots I: Introductionopen and closed dot regimes, Coulomb Blockade, quantum confinement energy, constant interaction model lecture notes: pdf articles: Kouwenhoven et al., dot review article, pp 1-28 pdf van Houten et al., CB review, NATO ASI, pp 1-15 pdf Foxman et al., PRB47, 10020 (1993) pdf Foxman et al., PRB50, 14193 (1994) pdf | |

jan 10, wed, 10:15am | (cont.)quantum dots I: IntroductionCoulomb diamonds, ground state and excited state spectroscopy, sequential and cotunneling transport, Coulomb peak lineshapes lecture notes pdf quantum dots II: Open Dotsopen dot regime, conductance fluctuations, weak localization, phase coherence, lecture notes pdf literature: A. Huibers, Ph. D. Thesis (1999) and S. Cronenwett, Ph. D. Thesis (2001) are available on the marcuslab webpage. open dot regime Huibers et al., PRL83, 5090 (1999) pdf | |

jan 17, wed, 10:15am | (cont.)quantum dots II: Open Dotsrandom matrix theory, spin-orbit coupling in semiconductors and quantum dots, weak antilocalization lecture notes pdf quantum dots III: Kondo Effect Kondo effect (metals, quantum dots), Kondo screening cloud, zero bias peak, logarithmic temperature dependence, even-odd structure lecture notes pdf Kondo effectGoldhaber-Gordon et al., Nature 391, 156 (1998) pdf Cronenwett et al., Science 281, 540 (1998) pdf | |

jan 24, wed, 10:15am | <quantum dots IV: Few Electron Dotslateral / vertical few electron structures, circular symmetry: shell filling, Fock-Darwin states, Singlet-Triplet states, Singlet Triplet ground state transition, lecture notes pdf Few Electron DotsTarucha et al., PRL77, 3613 (1996) pdf Ciorga et al., PRB61, 16315 (2000) pdf Kouwenhoven et al., Science 278, 1788 (1997) pdf Kouwenhoven, Austing & Tarucha, RPP 64, 701 (2002) pdf double quantum dotsdouble quantum dots, honey comb stability diagrams, finite bias transport, anticrossings lecture notes pdf | |

jan 31, wed, 10:15am | presentations I 1. charge sensing, Frank Freitag 3. singlet tripet states, Jan Brunner 4. spin blockade, Peter Noy | |

feb 7, wed, 10:15am | presentations II5. spin relaxation I, Roger Serra 6. spin relaxation II, Florian Schweizer 8. single spin readout, Alex Willand | |

feb 14, wed, 10:15am | presentations III10. spin manipulation, Alex Eichler 11. spin resonance, Charulata Barge |

topic | refs |
---|---|

1. charge sensing | Field et al., PRL70, 1311 (1993) pdfElzerman et al., PRB 67, 161308R (2003) pdf DiCarlo et al., PRL 92, 226801 (2004) pdf |

2. charge manipulation | Hayashi et al., PRL91, 226804 (2003) pdf Petta et al., PRL 93, 186802 (2004) pdf |

3. singlet triplet states | Kyriakidis et al., PRB66, 35320 (2002) pdfZumbuhl et al., PRL 93, 256801 (2004) pdf |

4. spin blockade | Ono et al., Science 297, 1313 (2002) pdfJohnson et al., PRB 72, 165308 (2005) pdf |

5. spin relaxation I | Fujisawa et al., Nature 419, 278 (2002) pdfHanson et al., PRL 91, 196802 (2003) pdf |

6. spin relaxation II | Kroutvar et al., Nature 432, 81 (2004) pdfAmasha et al., cond-mat/0610679 (2006) pdf |

7. spin filtering | Potok et al., PRL89, 266602 (2002) pdfFolk et al., Science 299, 679 (2003) pdfHanson et al., PRB 70, 241304R (2004) pdf |

8. single spin readout | Elzerman et al., Nature 430, 431 (2004) pdfHanson et al., PRL 94, 196802 (2005) pdf |

9. nuclear spins | Johnson et al., Nature 435, 925 (2005) pdfKoppens et al., Science 309, 134 (2005) pdf |

10. spin manipulation | Petta et al., Science 309, 2180 (2005) pdf |

11. spin resonance | Koppens et al., Nature 442, 766 (2006) pdf |

**books**

“*Mesoscopic Electronics in Solid State Nanostructures*”, Thomas Heinzel, Wiley-VCH (2003)

“*Electronic Transport in Mesoscopic Systems*”, Supriyo Datta, Cambridge Universy Press (1995)

“*The Physics of Low-Dimensional Semicond.*”, John H. Davies, Cambridge University Press (1998)

**review articles**

“*Quantum Transport in Semiconductor Nanostructures*”, C. W. J. Beenakker and H. van Houten, published in Solid State Physics, 44, 1-228 (1991) (out of print, available at arXive:cond-mat/0412664) pdf

“*Electron Transport in Quantum Dots*”, L. P. Kouwenhoven, C. M. Marcus, P. L. McEuen, S. Tarucha, R. M. Westervelt and N. Wingreen, NATO ASI conference proceedings, edited by L. L. Sohn, L. P. Kouwenhoven and G. Schön (Kluwer, Dordrecht, 1997). pdf

“*Coulomb Blockade Oscillations in Semiconductor Nanostructures*”, H. van Houten, C. W. J. Beenakker and A. A. M. Staring, published in *Single Charge Tunneling*, edited by H. Grabert and M. H. Devoret, NATO ASI series B294 (Plenum, New York, 1992), (out of print, available at arXive:cond-mat/0508454). pdf

“*Few-Electron Quantum Dots*”, L. P. Kouwenhoven, D. G. Austing and S. Tarucha, Rep. Prog. Phys. **64**, 701 (2001). pdf

“*Recipes for Spin Based Quantum Computing*”, V. Cerletti, W. A. Coish, O. Gywat and D. Loss, Nanotechnology **16**, R27 (2005). pdf