Physics Professor Receives NSF Grant To Develop Light Measuring Instrument

Albion College physics professor Aaron Miller is one of the principal investigators on a project that received $900,000 in National Science Foundation funding to develop an instrument to measure individual particles of light to do “quantum computing.”

Working in collaboration with Professor Olivier Pfister of the University of Virginia and Dr. Sae Woo Nam at the National Institute of Standards and Technology, the goal is the development of high-performance transition-edge sensor superconducting photodetectors which could spur improved speed in computers.

“Quantum computing has an overarching goal of exploring an alternate model of how we do computation in the hope of that computing keeps pace with the advances that it has made throughout history,” Miller explained. “Moore’s Law is an empirical law that says that the number of transistors you can put onto a computer chip doubles every 24 months. It has been the history since modern computers were created that the transistors have been shrinking, the speed of the computer and the size of the memory has been going up, and all of this has been keeping pace with Moore’s law, which has been phenomenal.

“Eventually we run into a problem with physics,” Miller added. “You run into the hard limit where you can’t make the transistor any smaller. We’re dealing with transistors that use hundreds of electrons to switch them. Eventually you run into the quantum behavior of atoms. Quantum Computing attempts to exploit that behavior to continue our historical computational growth.”

Miller also noted that while a quantum computer doesn’t yet exist, a number of quantum computer “programs” have been developed. Research projects have received significant funding because of the implications on defense and national security. Quantum computers have the ability to factor numbers quickly which has implications for cracking security codes.

“Codes that banks use to encrypt your information to make transfers are using encryption algorithms which are based on computational complexity,” Miller said. “A classical computer cannot break this code for 100 years, but a quantum computer could break it much faster.”

Pfister has combined theory with experimentation to publish work on manipulating light for quantum computing. Light could be the key component for quantum computers because it is easier to prevent unwanted errors in the quantum system using light than with the electrical systems in use in today’s computers. The quanta of light (photons) are able to be prepared in a way that keeps them “pure” because they interact only slightly with other photons and materials.

“The field of experimental quantum computing is so wide open that nobody knows what technology is going to win,” Miller said. “It’s possible that the computers of the future, the big super-computers, will be laser based. It’s possible they could be superconducting electronics. It’s possible they could be solid-state silicon the way we do other stuff. The problem is when you get away from conventional computing – you get away from the transistor and the silicon – and the best system to use to develop the quantum transistor is not known.”

Miller, who worked at NIST after completing his Ph.D. in 2001, and Nam have experience developing instrumentation to measure light. The excitement now is to apply this experience to developing a system for quantum computing. Miller will travel to the NIST lab in Boulder, Colo., this summer to modify a photon detection instrument that has already been created. He will bring the system back to Albion where Miller can work with students on upgrading the instrument to support Pfister’s study. The third year of the grant will include installation of a newly developed instrument at UVa.

“We’ve made instruments like this in the past and we have a very good idea that this will succeed,” Miller said. “We understand the application once the device is built, but there is a research component which is how do we take our existing detector technology that we’ve made in the past and push it for use in an exciting new application.”