Professor, Electrical and Computer Engineering

Research interests: terahertz; quantum cascading lasers; nanophotonics; nanofabrication; SPM


Professor Dayan Ban was one of the leading researchers who developed and prototyped the first wafer-fused infrared optical up-converter and the first pixelless infrared optical up-conversion imaging device. He also pioneered the research in scanning probe microscopy and invented scanning differential spreading resistance microscopy technique.

Ban and his group are currently investigating how to improve the device efficiency of hybrid organic/inorganic devices, experimentally measure the active-region temperature of lasing terahertz quantum cascade lasers, directly observe thermal lasing quenching of terahertz quantum cascade lasers, and apply time-domain terahertz spectroscopy to study the device physics of terahertz quantum cascade lasers.

At the National Research Council’s Institute for Materials Science, Ban and his colleagues demonstrated terahertz (THz) quantum-well-cascade lasers with lasing wavelength at 104 micrometers (~2.9 THz in frequency) and experimentally studied the doping effect in THz quantum cascade lasers – pinpointing the balance between free carrier absorption loss and optical gain. Ban was a visiting scientist at Nortel in 2001-2002, where he and his colleagues developed and applied novel scanning probe microscopy techniques. The nano-probing techniques were deployed to observe two-dimensional profiles of the electrical potential and conductivity within actively driven devices, with nanometer spatial resolution.


  • PhD, University of Toronto, 2003

  • MSc, University of Science and Technology of China, China, 1995

  • BSc, University of Science and Technology of China, China, 1993

Dayan Ban

    University of Waterloo