Electronic and Structural Properties of LaNiO₃-Based Heterostructures (eBook)

Jennifer Fowlie obtained her Master in physics in 2013 from the University of St Andrews before pursuing graduate studies at the University of Geneva. While in Geneva she worked mostly on growth of nickelate based heterostructures and their characterisation by various means.

Supervisor’s Foreword 7
Acknowledgements 10
Contents 12
1 Introduction to Perovskite Oxides 15
1.1 Structure 15
1.2 Properties 18
References 22
2 Introduction to Thin Film Physics 23
2.1 What is a Thin Film? 23
2.2 Challenges 25
2.3 Thin Film Perovskite Oxides 27
References 30
3 Introduction to the Nickelates 32
3.1 The Rare Earth Nickelates 32
3.2 Electronic Configuration 32
3.3 The Nickelate Phase Transitions 33
3.3.1 The Metal-Insulator Transition 33
3.3.2 The Néel Transition 34
3.3.3 The Structural Transition 35
3.4 Thin Film Nickelates 36
3.5 LaNiO3 37
3.5.1 Magnetic Order in LaNiO3 37
3.6 The Motivation Behind LaNiO3-Based Heterostructures 38
References 41
4 Experimental Techniques 44
4.1 Thin Film Growth 44
4.1.1 RF Off-Axis Magnetron Sputtering 45
4.2 Thin Film Characterisation 49
4.2.1 Atomic Force Microscopy 49
4.2.2 X-Ray Diffraction 50
4.2.3 Resonant Soft X-Ray Diffraction 53
4.2.4 DC Electronic Transport Versus Temperature 56
4.2.5 Magnetotransport 56
4.2.6 Hall Effect 57
4.2.7 Photolithographic Patterning 57
4.2.8 Raman Spectroscopy 58
4.2.9 Scanning Transmission Electron Microscopy 60
References 60
5 Quantifying Octahedral Distortions in Perovskites 62
5.1 The Importance of Structure 62
5.2 Octahedral Distortions 62
5.3 Geometric Considerations 63
5.4 Simulating Diffraction Patterns 64
5.5 Measurement of Half-Integer Diffraction Peaks 66
5.6 Application to Perovskite Films 68
5.6.1 LaAlO3/SrTiO3 68
5.6.2 LaNiO3 Thickness Dependence 71
5.7 Summary 75
References 75
6 Ultrathin LaNiO3 78
6.1 Motivation 78
6.2 Electronic Transport 78
6.3 Raman Spectroscopy 82
6.4 Density Functional Theory Approach 84
6.5 Scanning Transmission Electron Microscopy 85
6.6 The Parallel Conductor Model 86
6.7 Discussion 87
6.8 Summary 89
References 89
7 The Nd1-xLaxNiO3 Solid Solution 91
7.1 Motivation 91
7.2 Valence Skipping Elements 91
7.3 Negative U-Mediated Superconductivity 93
7.4 Growth of Solid Solution Thin Films 94
7.5 Probing the Phase Diagram 96
7.5.1 The Metal-Insulator Transition 96
7.5.2 The Néel Transition 98
7.5.3 The Structural Transition 98
7.6 The Search for Superconductivity 104
7.6.1 Low Temperature Transport 104
7.6.2 Efforts Towards Carrier Doping 105
7.7 Summary 105
References 106
8 Conclusions and Perspectives 108
Curriculum Vitae 110