Chapter 1. Introduction to the Advanced Materials for Future Teraheretz Devices, Circuits and Systems.- Chapter 2. Gallium Nitride Based Solid-State Devices for Terahertz Applications.- Chapter 3. Noncontact Characterization Techniques of GaN-Based Terahertz Devices.- Chapter 4. A Brief Review on Terahertz Avalanche Transit Time Sources.- Chapter 5. Terahertz IMPATT Sources Based on Silicon Carbide.- Chapter 6. Terahertz Quantum Dot Intersublevel Photodetector.- Chapter 7. Graphene - A Promising Material for Realizing Active and Passive Terahertz Radiators.- Chapter 8. First-principle Molecular Dynamics Simulation of Terahertz Absorptive Hydrogenated TiO2 Nanoparticles.- Chapter 9. Doping Effects on Optical Properties of Titania Composite in Terahertz Range.- Chapter 10. Silicon Nanowires as a Potential Material for Terahertz Applications.- Chapter 11. Analysis of Optical Performance of Dual-order RAMAN Amplifier beyond 100 THz Spectrum.- Chapter 12. A Novel Approach Dual Material Double Gate Germanium based TFET.- Chapter 13. Sources and Security Issues in Terahertz Technologies.- Chapter 14. Interferometric Switch Based on Terahertz Optical Asymmetric Demultiplexer.- Chapter 15. Material Systems for Realizing Heterojunction IMPATT sources for Generating Terahertz Waves.