Research
Over the last few years, researchers around the world have been pursuing a new direction for high-performance semiconductor technologies, including lasers, photonic devices, electronic logic, and even new computers using quantum information, that would operate based on a quantum mechanical property of the electron called "spin". By virtue of this spin property, an electron acts as a tiny magnet, and spin-based semiconductor devices will work by controlling the direction in which the magnet is oriented. For example, digital information (the 0's and 1's of binary logic) can be stored in electron spin for a new generation of logic devices. New light-emitting diodes and lasers may be fabricated based on currents of electron spins. These spin-based light sources, which would produce circularly-polarized light, would be useful in a variety of situations in spintronic devices and circuits and in schemes for spin-based quantum computation (e.g. spin interconnect, optical spin control, etc.) Extremely fast optical switching technology for communication systems may also be possible using coherent precession of a collection of electron spins in a semiconductor nanostructured material. These new "spin" technologies (and others that have not yet been envisioned) would have a considerable economic impact in many areas of modern industry.
My research is focused on the measurement and control of electron spin dynamics and spin coherence in semiconductor nanostructures. The dynamic characteristics of the electron spin system are of crucial importance for any spin-related device application. Semiconductor nanostructures currently under investigation include InAs quantum dots and InAs/GaSb/AlSb heterostructures, which exhibit strong spin-orbit effects and are of interest for spin-based photonic technologies, quantum computation, and spin transistor devices. The dynamics of electron spins in these nanostructures are studied using femtosecond laser pulses in a new state-of-the-art ultrafast laser facility at Dalhousie University.
Students who are interested in working with me will gain advanced knowledge and technical skills in ultrafast laser technologies and the physical properties of semiconductor nanostructures, assets that will be valuable in a number of rapidly advancing high technology areas, including spintronics, photonics and semiconductor device technology.