UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl)
UvA-DARE (Digital Academic Repository)
Experimental investigation of potential topological and p-wave superconductors
Trần, V.B.
Publication date
2014
Link to publication
Citation for published version (APA):
Trần, V. B. (2014). Experimental investigation of potential topological and p-wave
superconductors.
General rights
It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons).
Disclaimer/Complaints regulations
If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible.
Contents
Abbreviations
Chapter 1 Introduction... 1
1.1 General introduction... 2
1.2 Outline of the thesis... 3
References ... 6
Chapter 2 Experimental background and techniques ... 9
2.1 Sample preparation... 10
2.2 Sample characterization... 10
2.3 Cryogenic techniques ... 10
2.4 Calibration of RuO2 thermometers in high magnetic field... 12
2.5 Experimental techniques ... 13
2.5.1 Electrical resistivity experiment ... 13
2.5.2 AC-susceptibility experiment... 14
2.5.3 High pressure experiment ... 14
2.5.4 SR experiment ... 16
2.6 Data acquisition and analysis... 16
References ... 17
Chapter 3 Theoretical aspects ... 19
3.1 Ferromagnetic superconductors ... 20
3.1.1 Quantum criticality ... 20
3.1.2 Ferromagnetic superconductors... 22
3.2 Topological insulators and superconductors ... 25
3.2.1 Topological insulators... 25
3.2.2 Topological superconductors ... 31
3.2.2.1 Odd and even-pairing superconductors... 31
3.2.2.2 Topological superconductors... 32
3.3.1 Slope of the upper critical field Bc2(T)... 34
3.3.2 Temperature variation of the upper critical field Bc2(T) ... 35
References ... 37
Chapter 4 Possible p-wave superconductivity in the doped topological insulator CuxBi2Se3... 43
4.1 Introduction... 44
4.2 Sample preparation... 45
4.3 AC-susceptibility ... 46
4.4 Electrical resistivity... 47
4.5 Upper critical field Bc2 at ambient pressure... 48
4.6 Superconducting transition under pressure... 50
4.7 Upper critical field Bc2 under pressure ... 52
4.8 Discussion... 57
4.9 Conclusion ... 58
References ... 59
Chapter 5 Unconventional superconductivity in the noncentrosymmetric Half Heusler YPtBi... 61
5.1 Introduction... 62
5.2 Sample preparation and characterization... 63
5.3 Low-field experiments ... 64
5.3.1 Sample characterization ... 64
5.3.2 Low-field magnetization and AC-susceptibility ... 65
5.3.3 Muon spin relaxation and rotation... 68
5.3.4 Discussion ... 70
5.4 High pressure experiments ... 71
5.4.1 Resistivity... 71
5.4.2 Upper critical field Bc2... 73
5.5 Conclusion ... 77
References ... 79
Chapter 6 Angular variation of the magnetoresistance of the superconducting ferromagnet UCoGe ... 81
6.1 Introduction... 82
6.3 Magnetoresistance... 84
6.4 Upper critical field Bc2... 86
6.5 Discussion... 88 6.6 Conclusion ... 90 References ... 92 Summary ... 95 Samenvatting... 98 List of publications... 101 Acknowledgements... 103
