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Ultrafast Terahertz Spectroscopy and Imaging

Ti-sapphire kilohertz laser system which generates 2 watts at 805 nm 40 fs pulses for time-resolved THz spectroscopy (TRTS, background table). The regenerative amplifier (center) is pumped by a 20 watt nanosecond laser. The OPA (foreground) is used to generate tunable visible and near-infrared excitation pulses for pump-THz probing of photovoltaics as well as mid-IR probes for the TRIR apparatus.
Three independent femtosecond laser systems are used for generating ultrafast pulses in the mid-IR and Terahertz (THz) spectral regions through the UV; infrared, THz and visible multi-element focal plane array cameras and instrumentation for capturing images and transient spectra of samples with a single laser pulse; detection systems capable of making accurate time-resolved amplitude and phase measurements on THz pulses as they interact with samples.

Apparatus includes two femtosecond solid-state laser systems that are CW Diode pumped (YVO4) with 20-femtosecond Ti: sapphire oscillators and KHz Ti: sapphire regenerative amplifiers with mid-IR Optical Parametric Amplifiers (OPA) and nonlinear crystals for generating ultrafast pulses in the far-IR through UV; visible near-IR CCD and bolometer multichannel detector arrays and instrumentation for directly capturing images and transient spectra by up-converted THz images of samples.

Time-resolved THz spectrometer for spectral measurements of samples (0.2 to 10 THz) and transient spectroscopy of bimolecular, photovoltaic, and materials characterization.
Terahertz imaging apparatus employing high-power pulsed GaAs antenna or Lintium Niobate generators and object transmission and reflection geometries for direct imaging and hyperspectral studies relevant to homeland security applications.

Created May 3, 2011, Updated November 15, 2019