In Douglas Adams’ book, The Hitchhiker’s Guide to the Galaxy, Deep Thought was a city-sized computer created by a pan-dimensional super-intelligent race of beings that was tasked with coming up with the Answer to The Ultimate Question of Life, the Universe, and Everything. After seven and a half million years of calculation, the rather disappointing answer to this vast “question” was…42. Having checked the answer thoroughly, and being certain that it was correct, Deep Thought tells the crestfallen recipients of the answer “I think the problem, to be quite honest with you, is that you’ve never actually known what the question was.”
The Ultimate Question of Life, the Universe, and Everything is a bit esoteric, and as Adams’ book intimates, no computer, no matter how long it operates for, will ever come up with an answer to such an existential question. But, what if you could calculate the answer to a more “mundane,” yet important question that you cannot answer today, and do it in just a fraction of the time? What if you could encrypt communications in such an unbreakable manner that you would never have to worry about computer security ever again? What if you could interrogate the deepest mysteries of quantum mechanics to design new materials and processes to provide infinite fusion energy to the planet? What if you could design new drugs to cure diseases for which we have no permanent answers today? What if you could answer those intractable questions and somehow know what is currently unknowable?
Quantum physics. Quantum information. Quantum computer. The word “quantum” stirs up all kinds of descriptors – fast, small, huge, powerful, nano, uncertain, entangled, invisible, discrete — some more useful than others. Just what is a quantum computer, quantum information, or, for that matter, quantum science? Why are we hearing so much more about it now? Isn’t it just the purview of dorky, bespectacled scientists huddled around expensive machinery in dark, underground labs? The answer to the last question is a resounding NO. Quantum science is experiencing a surge of interest as researchers, students, and industry leaders across the globe race to build a truly usable quantum computer, a machine that will be able to process unimaginable amounts of data at exponentially faster rates than today, transfer and store information with advanced cryptography, and facilitate new discoveries and myriad other applications.
Quantum theory has been around since the turn of the 19th century, ushered in by the names we all remember from chemistry and physics class — Planck, Einstein, Bohr, Heisenberg, and Schrödinger, amongst others. Modern quantum mechanics attempts to describe the physical world at the atomic and subatomic level and how the physical systems at that level behave. The goal of quantum computing is to leverage the bizarre quantum mechanical rules of physics at the subatomic level to solve problems much faster than a conventional computer.
A “bit” of information in a traditional computer is either a one or a zero, on or off. Each bit can only exist in one state at a time. A quantum bit, or “qubit,” can be both a one and a zero at the same time, due to the quantum character of “superposition.” This effectively doubles the computing power of one traditional bit. Two qubits together can represent four scenarios at the same time, three qubits represent eight scenarios, and so on. The computing power thus grows exponentially with the number of qubits. The other feature of quantum mechanics that can be exploited is “entanglement,” what Einstein called “spooky action at a distance.” Entanglement is a phenomenon that shows that particles can be linked together, and the effects of manipulation of one particle are shown in the other, no matter the distance between them. Spooky, maybe. Exploitable? Definitely. Who will be capitalizing on this and how it will be done has become a matter of national importance.
On September 24, in Washington, D.C., the White House Office of Science and Technology Policy hosted a summit on Quantum Information Science. Participants included representatives from industry, academia, government agencies, and foundations. The event coincided with the unveiling of the national strategic overview for quantum science released by the National Science and Technology Council. OSTP and the Office of Management and Budget identified in their Research and Development Memo that quantum science is a key priority area of investment for the administration and federal agencies. Whilst the government focus will be on supporting much needed basic research, the private sector and academia need to tightly integrate basic research and engineering to create practical quantum computers and other quantum information systems.
I had the opportunity to participate in the summit representing Purdue University and applaud the initiative that the administration, the federal agencies, Congress, and the private sector are demonstrating in this critical area. Quantum Information Science will no doubt become a defining technology for the future of humankind, and a strong, early, and coordinated multi-sector focus on these technologies is essential for the U.S. to sustain its economic and national security leadership.
The National Science Foundation, the DOE Office of Science, NIST and the DOD are focused on enabling research and development in Quantum Information Science, and the new strategic programs they intend to focus on and fund in the future. In addition, leaders of various technology giants such as IBM, Microsoft, Google, Intel, Lockheed, and others are developing the technologies to build the quantum computers and systems of the future, including very interesting and effective partnerships with universities such as Purdue. Public-private partnerships will need to provide test beds and benchmarking mechanisms for new QIS technologies as they are developed.
As a prime example of such a partnership, Purdue University and Microsoft Corp. signed a five-year agreement to develop a sturdy and scalable quantum computer. The team, assembled by Microsoft, works at Discovery Park’s Birck Nanotechnology Center on developing a topological quantum computer that is especially robust against decoherence, and therefore is theoretically more stable and less error-prone. The Purdue group, led by physics professor Michael Manfra, grows and studies ultra-pure semiconductors and hybrid systems of semiconductors and superconductors that may form the physical platform upon which a quantum computer is built. Microsoft employees are embedded in the Purdue research team, and collaboration exists between Purdue, Microsoft, and experimental research sites located in universities here and abroad.
Purdue has other points of light to share in the Quantum Information arena. As light and matter are so sensitive to disturbance, it would be virtually impossible for a hacker to do their work undetected in a quantum system, and now we are one step closer to unhackable communication thanks to the work of the research team of Vlad Shalaev, a distinguished professor of Electrical and Computer Engineering. Shalaev’s pre-eminent nanophotonics team has created a new technique that increases the secret bit rate of photons to allow for sending much larger pieces of information on a single photon than has been previously demonstrated. More information, faster and safer.
Other Purdue researchers have received Federal grants for their work in Quantum science. Both the National Science Foundation and the Office of Science at the Department of Energy are supporting Quantum Information Science and, as detailed in the hyperlinked news release, Purdue faculty from the colleges of Engineering and Science have been funded to work on topics ranging from photon entanglement and development of photonics chips to spin-based quantum control, to the application of quantum information science to high energy physics and the development of new quantum computing algorithms for materials discovery.
The importance of Quantum Information Science—computing, communications, sensors, etc.—cannot be stressed enough, and we cannot afford to fall behind in this important science, technology, and engineering race. The few examples above are representative of the wide range of work ongoing at Purdue in this area. Many other universities across the nation have similar or even larger efforts already underway, and at Purdue, we need to focus and coordinate across the entire campus to provide a well-coordinated and effective platform from which to continuously increase the impact of our work in this important space. I am optimistic that following on this important White House summit, momentum will continue to grow and that the collective creativity and innovation spirit of all of the public and private efforts already underway and those new ones that will be created going forward, will be integrated and harnessed to create, very soon, the practical and commercial Quantum Information Systems that will define the future of competitiveness of the United States in everything, from commerce, to science, to defense, and many other sectors. Here at Purdue University, we are committed to driving this vision forward, and building on our collective strengths we will work to make the Quantum revolution a reality.