Ulteriori informazioni
Recent advances in the fabrication of semiconductors have created almost un limited possibilities to design structures on a nanometre scale with extraordinary electronic and optoelectronic properties. The theoretical understanding of elec trical transport in such nanostructures is of utmost importance for future device applications. This represents a challenging issue of today's basic research since it requires advanced theoretical techniques to cope with the quantum limit of charge transport, ultrafast carrier dynamics and strongly nonlinear high-field ef fects. This book, which appears in the electronic materials series, presents an over view of the theoretical background and recent developments in the theory of electrical transport in semiconductor nanostructures. It contains 11 chapters which are written by experts in their fields. Starting with a tutorial introduction to the subject in Chapter 1, it proceeds to present different approaches to transport theory. The semiclassical Boltzmann transport equation is in the centre of the next three chapters. Hydrodynamic moment equations (Chapter 2), Monte Carlo techniques (Chapter 3) and the cellular au tomaton approach (Chapter 4) are introduced and illustrated with applications to nanometre structures and device simulation. A full quantum-transport theory covering the Kubo formalism and nonequilibrium Green's functions (Chapter 5) as well as the density matrix theory (Chapter 6) is then presented.
Sommario
1 Introduction.- 1.1 Introduction.- 1.2 What are Nanostructures?.- 1.3 Physical Length Scales in Transport.- 1.4 Hierarchy of Modelling Approaches.- 1.5 Scope of This Book.- 2 Hydrodynamic simulation of semiconductor devices.- 2.1 Introduction.- 2.2 Statistical Averages and Moments of the Bte.- 2.3 The Hydrodynamic Model.- 2.4 Model Coefficients.- 2.5 Examples of Application to Hot-Carrier Effects.- 3 Monte Carlo simulation of semiconductor transport.- 3.1 Introduction.- 3.2 Semiclassical Transport in Semiconductors.- 3.3 The Monte Carlo Method for Bulk Transport.- 3.4 Results.- 3.5 From Semiclassical to Quantum Transport.- 3.6 Conclusions.- 4 Cellular automaton approach for semiconductor transport.- 4.1 Introduction.- 4.2 Examples of Cellular Automata in Fluid Dynamics.- 4.3 Full Boltzmann Transport Equation as Cellular Automaton.- 4.4 Validation and Comparison with Monte Carlo Results.- 4.5 Comparison with Experiment.- 4.6 Summary.- 5 Quantum transport theory.- 5.1 Introduction.- 5.2 Coulomb Drag.- 5.3 Kubo Formula for Transconductivity.- 5.4 Impurity Scattering.- 5.5 Coulomb Drag in a Magnetic Field.- 5.6 Summary of Coulomb Drag.- 5.7 Nonequilibrium Green's Function Techniques.- 5.8 Model Hamiltonian.- 5.9 Calculation of the Tunnelling Current.- 5.10 Noninteracting Resonant-Level Model.- 5.11 Resonant Tunnelling with Electron-Phonon Interactions.- 6 Density matrix theory of coherent ultrafast dynamics.- 6.1 Introduction.- 6.2 Density Matrix Formalism.- 6.3 Interaction with an External Field.- 6.4 Carrier-Phonon Interaction.- 6.5 Carrier-Carrier Interaction.- 6.6 Multiple Interactions.- 6.7 Results.- 6.8 Conclusions.- 7 Dynamic and nonlinear transport in mesoscopic structures.- 7.1 Introduction.- 7.2 Theory.- 7.3 Examples.- 7.4 Conclusion.- 8 Transport in systemswith chaotic dynamics: Lateral superlattices.- 8.1 Introduction.- 8.2 Experiments.- 8.3 Classical Chaos and Transport.- 8.4 Quantum-Mechanical Band Structure.- 8.5 Quantum Signatures of Chaos.- 8.6 Quantum Transport.- 8.7 Summary and Outlook.- 9 Bloch oscillations and Wannier-Stark localization in semiconductor superlattices.- 9.1 Introduction.- 9.2 Historical Background.- 9.3 Theoretical Analysis.- 9.4 Two Equivalent Pictures.- 9.5 Some Simulated Experiments.- 10 Vertical transport and domain formation in multiple quantum wells.- 10.0 Introduction.- 10.1 The Different Transport Regimes.- 10.2 Transport between Weakly Coupled Quantum Wells.- 10.3 Formation of Field Domains.- 10.4 Imperfect Superlattices.- 10.5 Oscillatory Behaviour.- 10.6 Details of the Calculations.- 10.7 Conclusions.- 11 Scattering processes in low-dimensional structures.- 11.1 Introduction.- 11.2 The Scattering Rate.- 11.3 Optical Phonons in a Quantum Well.- 11.4 Acoustic Phonons.- 11.5 Charged Impurities.- 11.6 Interface Roughness Scattering.- 11.7 Alloy Scattering.- 11.8 Other Scattering.
