Professor David Cory exploring QIP theory

“If you can change the rules in a fundamental way, you can propose to do truly outrageous things.” says David Cory, Professor of Nuclear Science & Engineering. He’s talking about the science of Quantum Information Processing (QIP), a means of designing tools that operate on the basis of quantum mechanics rather than classical everyday physics.

The usual example is the quantum computer. Such a computer might work by treating each particle as a single quantum bit, each with their computational state determined by the direction the particle’s spin. This would allow a small group of such particles to act like a CPU, and by exploiting quantum interference they could exceed the performance of anything operating with today’s chip technology. The trick is finding ways to correct the errors that inadvertently arise and to do so for a relatively large number of particles.

A device controlling as few as 21 particles would match the performance of today’s best desktop PC, while about 35 particles would outperform the best supercomputer. “It scales up very quickly.” He says, “The problem is that quantum computers today are also exponentially harder to build.”

The Cory lab is currently working on a test bed for exploring QIP theory through experimentation and testing. His target for this device is 15 particles. Although simulations of this type of device have been done, they are not complete. “There’s a lot going on down there,” says Cory.

Other applications of this quantum thinking would take measurements or act as actuators. In fact, students from the NSE undergraduate course 22.033, Nuclear Systems Design Project, took on the task of designing a neutron interferometer that uses quantum techniques to effectively cancel out noise from mechanical vibrations. Changes proposed in this design would make such instruments thirty times more sensitive and much more precise. It’s the kind of outrageous change that would enable new types of physics, and is made possible by looking at the problem through the lens of quantum physics. That group is one of the finalists for this year’s American Nuclear Society Student Design Competition.

These types of changes using the quantum perspective have the potential to enable new types of physics and engineering. Professor Cory’s group and these NSE students are taking the first steps in that direction.