Station Q Purdue: Quantum Semiconductor Systems
The Manfra Group focuses on the quantum-mechanical properties of electrons in ultra-high purity III-V semiconductor devices and is affiliated with the Department of Physics and Astronomy, School of Materials Engineering, the School of Electrical and Computer Engineering, and Birck Nanotechnology Center at Purdue University.
To build nanostructures needed for our experiments, we devote significant resources to a high-purity growth technique known as molecular beam epitaxy (MBE). MBE allows us to build semiconductor structures one atomic layer at a time and thus engineer the electronic energy levels to suit our needs. As practiced in our group, MBE allows for exploration of correlated electron motion in materials with very low residual disorder. We can build a two-dimensional electron gas (2DEG) in which the mean free path approaches 0.4 mm at low temperatures!
We study quantum transport in our low-temperature laboratory where we can cool 2DEGs below T=15mK at high magnetic fields. Ongoing projects include study of exotic topological phases in the fractional quantum Hall regime and development of novel devices for spin-based quantum bits (qubits). Much of our effort is presently directed towards semiconductor-based quantum computing; we are fortunate to collaborate with many of the leading groups around the world in this exciting field.
Most recently, we have launched Station Q Purdue—signifying our strong collaboration with Microsoft Research Station Q. We are constructing a new deposition system that combines MBE growth of high spin-orbit coupling III-V semiconductors with superconducting metals to engineer hybrid materials capable of hosting Majorana fermions. We collaborate with the experimental groups in Copenhagen, Delft, and Sydney in this effort.