Machine Construction and Design


  • Design and implentation of an integrated mass spectrometer for the research of clusters and small molecules

This spectrometer consists of a cluster source, such as a magnetron sputtering cluster source, a de Heer Low temperature pulsed laser vaporization cluster source, or an electrospray ionization source, a radio frequency multi-stage quadrupole ion trap, a a multi-reflectron TOFMS, a second-rder focusing VMI system with angular resolved photoelectron spectroscopy and position sensitive TOF capabilities, and a molecular beam E-H-gradient deflection device. The projected achievable mass resolutions are m/Δm = 50,000 for charged clusters and m/Δm = 10,000 for neutral clusters.


  • Crossed molecular/cluster beam apparatus with 3D position-senstive TOFMS capability

Will include a de Heer low temperature pulsed laser vaporization cluster source and will boast three dimensional position sensitive time-of-flight detection. Projected spatial resolutions are 60 μm and 10 μm in the x and y directions, respectively. Achievable source temperatures will range from 4K to 300K. Projected achievable mass resolutions are m/Δm ≥ 10,000 for high-resolution position-insensitive mode and m/Δm ≥ 2000 for position sensitive mode.



Research Directions


  • Use of various kinds of semiconducting channel materials to develop a reliable method by which graphene tunneling junctions can be reproducibly fabricated in graphene nanoribbons (including ones with ballistic transport properties and ones with diffusive transport properties ) that can be characterized effectively. The semiconducting channel materials include semiconducting graphene, SiC/SiO2, and semiconducting materials grown by MOVPE.
  • We will develop a tunneling FET with a short channel top gate structure and split gate geometry.
  • Optimize the ultra-high frequency performance and/or ultra-low energy performance of the aforementioned devices.
  • Research on the physical and chemical properties of the clusters and nanoparticles based on molecular beams.
  • Phase transition research on the size-dependent water clusters and metal atom doped water clusters.
  • Research on the photoelectron spectra of Au clusters in different electron states
  • Research on the catalytic mechanism of heavy metal clusters.
  • Research on the photoelectron spectra of 3D transition metal clusters in different states
  • Research on solvent chemistry in restricted systems
  • Research on crossed cluster/molecular beams.