The Krauss Group:
The Krauss Group:
Nanoscale Materials and Devices
Nanoscale Materials and Devices
"Where Size Matters"

Research
Research Topics:

  • Semiconductor Nanocrystals
  • Pathogen Detection
  • Label-free DNA Microarray

  • Carbon Nanotubes
  • Ultrafast Electronics
  • Single Nanotube Spectroscopy
  • Single Protein Folding

  • Single Nanoparticle Spectroscopy
  • Force Microscopy of CdSe Nanorods
  • PbSe Nanocrystal Spectroscopy
  • Semiconductor Nanocrystal Photonics
    • Carbon Nanotube Ultrafast Electronics

    Libai's research involves using ultrafast nonlinear optical spectroscopy to investigate the optical and electronic properties of single-walled carbon nanotubes (SWNTs). Transient absorption spectroscopy was performed to study the electronic relaxation dynamics at the band-edge of semiconducting SWNTs. For the fist time, the radiative lifetime of the band-edge fluorescence for isolated SWNTs was determined.

    Normalized transient absorption of bundled SWNTs (triangles) and isolated SWNTs (circles) with the autocorrelation of the laser pulse (dashed line) with excitation at 1350 nm. The solid lines are curve fits with a bi-exponential function with time constants of 230 fs and 1 ps for the bundle sample and 330 fs and 2 ps for the isolated sample. Inset: transient absorption of bundled SWNTs at excitation wavelength of 1550 nm.