Title: Intense Terahertz-Matter Interactions with semiconductors and DNA Abstract: Terahertz (THz) waves, whose frequency range is defined roughly to be from 0.1 to 10 THz (or wavelengths from 30 μm to 3000 μm), lies between optics and microwaves. THz imaging and diagnostics have tremendous potential for applications in non-destructive testing and imaging, medical diagnosis and chemical and biological identification. Over the past two decades, there has been extensive progress in THz technologies, mainly propelled by the rapid progress in ultrafast laser technology and in microelectronics fabrication. For example, recent advances in the generation of intense THz pulses is stimulating new studies in nonlinear THz optics. In this talk, I will present two examples of intense THz-matter interaction, one with semiconductors, and the other with DNA. Refreshments will be served at 2:15 p.m. (BEFORE the seminar) in room MNO C211