Giant nonlinear response of terahertz nanoresonators on VO2 thin film.

Ultrafast Terahertz Gating of the Polarization and Giant Nonlinear Optical Response in BiFeO3 Thin Films.

Terahertz pulses are applied as an all-optical bias to ferroelectric thin-film BiFeO3 while monitoring the time-dependent ferroelectric polarization through its nonlinear optical response. Modulations in the intensity of the second harmonic light generated by the film correspond to on-off ratios of 220× gateable on femtosecond timescales. Polarization modulations comparable to the built-in stat...

Metal-insulator phase transition in a VO2 thin film observed with terahertz spectroscopy

Transmission Properties of the Periodic Structures Based on Graphene Nonlinear Optical Conductivity in a Terahertz Field

By developing the terahertz (THz) technology, in addition to generators and detectors of THz waves, the existence of some tools such as modulators and filters are needed. THz filters are important tools for various applications in the field of chemical and biological sensors. Linear and nonlinear optical properties of the graphene have attracted lots of attention. In fact graphene exhibits vari...

Physics Colloquium Thursday , February 19 th at 3 : 40 PM in SC 234 Featuring

Materials which optical and electrical properties can be dynamically tuned have potential applications in many areas including smart windows, ultrafast switches, spatial light modulators, reconfigurable metamaterials and frequency selective filters. Vanadium dioxide (VO2) has been envisioned as one of the most promising material to realize tunable optical devices for THz and NIR applications. V...

Optical and Nonlinear Optical Response of Light Sensor Thin Films

For potential ultrafast optical sensor application, both VO2 thin films and nanocomposite crystal-Si enriched SiO2 thin films grown on fused quartz substrates were successfully prepared using pulsed laser deposition (PLD) and RF co-sputtering techniques. In photoluminescence (PL) measurement c-Si/SiO2 film contains nanoparticles of crystal Si exhibits strong red emission with the band maximum r...