In a state-of-the-art femtosecond laser facility at Dalhousie University, Dr. Kimberley Hall is using ultrafast laser pulses to study electron dynamics in novel semiconductor materials.  Electrons are typically known for their negative charge, but an electron also has a quantum mechanical property called “spin” through which it acts as a tiny magnet.  It may be possible to develop new transistors, photonic devices, and even quantum computers in which information is encoded in the direction of the electron’s spin.  Dr. Hall’s research group is working to understand and control the electron spin’s direction with femtosecond time resolution.

Quantum dots are nanometre-sized pieces of a semiconductor material that can be used to trap a single electron.  The spin direction of a trapped electron could be used as the fundamental bit of information for future quantum computers – the qubit.  Dr. Hall uses femtosecond optical techniques to determine the time scale required for quantum calculations and is developing approaches to performing operations on spin qubits using ultrafast laser pulses.  Dr. Hall is also studying ultrafast processes in new semiconductor materials embedded with magnetic impurities, which may allow memory functions to be incorporated into traditional semiconductor transistors. 

By shedding light on the behaviour of electron spins in solids using ultrafast laser pulses, Dr. Hall and her colleagues are paving the way towards new high performance technologies that exploit electron spin.