High Energy Lab (Lab2 - A642)

In this laboratory, we have our highest energy femtosecond pulses of 5 mJ with a 1 kHz repetition rate from a Ti:Sapphire regenerative amplifier system. We utilize these powerful laser pulses to study nonlinear processes and to do pump-probe spectroscopy in different domains of the electromagnetic spectrum. By supercontinuum generation, we cover the visible to NIR spectrum ranging from 240 nm to 20 µm; by photoconductive antenna/waveguides, we generate THz radiation covering the millimeter region. With different experimental setups, including two-color pump-probe, transient absorption spectroscopy, and time-resolved optical pump terahertz probe time-domain spectroscopy, we studied charge and carrier dynamics in organic photovoltaic and 2D van der Waals materials [1-4]. Besides fundamental research, we also engage in the development of new technologies, for example, we work on development of THz radiation sources [5,6], and in biomedicine applications including wide-field temporal focused two-photon microscopy [7] and photo-stimulated drug delivery system [8].

 

MAJOR EQUIPMENT

  • Spectra Physics Spitfire Ace (800 nm, 1 kHz, 5 mJ, 70 fs)
  • Spectra Physics MaiTai (800 nm, 42 MHz, 19 nJ, 40 fs)
  • Newport Transient Absorption Spectrometer
  • Toptica FemtoFiber Pro NIR (780 nm @140 mW or 1560 nm @350 mW, 80 MHz, < 100 fs)

 

EXPERIMENTAL SETUPS

  • Transient absorption spectroscopy
  • Two color pump probe
  • THz time-domain spectroscopy and optical pump - THz probe
  • Laser ablation process
  • Wide field two-photon microscope
  • Micro pump probe