Papenkort, Thomas: Coherent and squeezed phonons in semiconductor quantum wells : simulating optically induced lattice dynamics. 2012
Inhalt
- Contents
- Abstract | Zusammenfassung
- Introduction
- 1 Phonons in quantum wells
- 2 Driving coherent phonons
- 2.1 State of the art
- 2.2 Quantum kinetic calculations: Correlation expansion
- 2.2.1 Density matrix formalism with correlation expansion
- 2.2.2 Dynamical variables and the in-plane homogeneity
- 2.2.3 Qualitative explanation for driving mechanisms
- 2.2.4 Equations of motion
- 2.2.5 Coulomb interaction and mean-field approximation
- 2.2.6 The spin degree of freedom
- 2.2.7 Decoherence processes: Spin relaxation and phonon decay
- 2.2.8 Singularity in the Coulomb coupling matrix
- 2.2.9 Singularity in the Fröhlich coupling matrix
- 2.3 Absorption spectra and the quantum confined Stark effect
- 2.4 Non-resonant coherent phonon generation
- 2.5 Resonant coherent phonon generation
- 3 Squeezed phonon states
- 3.1 State of the art
- 3.2 Lattice uncertainties and spatial averaging
- 3.2.1 Uncertainties and the Heisenberg uncertainty principle
- 3.2.2 Effects of limited spatial resolution
- 3.3 Quantum kinetics: Why we need a new method
- 3.4 Quantum kinetics: Order separation
- 3.4.1 State vector formulation
- 3.4.2 Spin degree of freedom
- 3.4.3 Truncating the hierarchy
- 3.4.4 Comparison with other hierarchy-truncation schemes
- 3.4.5 Density matrix formulation
- 3.4.6 Decoherence
- 3.5 Producing squeezed phonons
- 4 Conclusions
- 5 Appendix
- 5.1 Parameters
- 5.1.1 Material parameters for GaAs/AlAs wells
- 5.1.2 Structure and simulation parameters
- 5.1.3 Numerical parameters
- 5.2 Model Hamiltonian
- 5.3 Correlation expansion
- 5.4 Order separation
- List of symbols
- References