Contents

• Contents
• List of Tables
• List of Figures
• 1 Introduction
• 2 Muon Spin Rotation Spectroscopy
  • 2.1 Muons and Muon Beams
  • 2.2 Hardware for µSR Spectroscopy
    • 2.2.1 Time-Differential µSR
  • 2.3 Data Reduction
• 3 Cryocrystals as µSR Samples
  • 3.1 Cryostats and Techniques
  • 3.2 Growing Cryocrystals
  • 3.3 Properties of Solid Nitrogen
    • 3.3.1 Crystal Structures
    • 3.3.2 Librational Modes in Solid Nitrogen
• 4 Muonium formation in Insulators
  • 4.1 Models of Muonium Formation
  • 4.2 Muonium Formation and Electron Transport in Insulators
    • 4.2.1 Muonium in Solid Nitrogen
    • 4.2.2 Muonium in Neon
  • 4.3 µSR in Electric Fields
    • 4.3.1 Liquid Helium in an Electric Field
    • 4.3.2 Solid Nitrogen in an Electric Field
  • 4.4 Delayed Muonium Formation
  • 4.5 Implications of Delayed Muonium Formation for µSR
• 5 Quantum Diffusion I: Theory
  • 5.1 An Introduction to Quantum Diffusion in Insulators
  • 5.2 Renormalization of the One-Phonon Interaction
  • 5.3 Linear Coupling; One-Phonon Diffusion
  • 5.4 Barrier Fluctuations
  • 5.5 Quadratic Coupling: Two-Phonon Limited Diffusion
• 6 Quantum Diffusion II: Experimental Results
  • 6.1 Two-Phonon Quantum Diffusion
  • 6.2 Muonium Diffusion in KCl
  • 6.3 Experimental Results in Solid Nitrogen
  • 6.4 Numerical Calculations: Solid Nitrogen
  • 6.5 One-Phonon Quantum Diffusion in Solid Xe
  • 6.6 Experimental Results in Solid Xe
  • 6.7 Numerical Evaluation of 1-Phonon Diffusion Theory
  • 6.8 Activated Tunnelling From Excited States
• 7 Conclusions
  • 7.1 Muonium Formation via Electron Transport
  • 7.2 Quantum Diffusion in Insulators
• References
• A Muonium Spin Polarization Function
  • A.1 Transverse Field
  • A.2 Longitudinal Field Polarization
• B Numerical Integration of a Highly Oscillatory Function