2014 Munushian Lecture
Quantum Computers and Raising Schrödinger’s Cat
Quantum systems such as atoms can be used to store information. For example, we can store binary information in two energy levels of an atom by labeling the state with lower energy a “0” and the state with higher energy a “1.” However, quantum systems can also exist in superposition states, thereby storing both states of the bit simultaneously, a situation that makes no sense in our ordinary-day experience. This property of quantum bits or “qubits” potentially leads to an exponential increase in memory and processing capacity. It would enable a quantum computer to efficiently solve certain problems such as factorizing large numbers – an ability that could compromise the security of current encryption systems. A quantum computer would also realize an analog of “Schrödinger’s Cat,” a bizarre situation where a cat could be simultaneously dead and alive. Experiments whose goal is to realize a quantum computer based on laser manipulations of atomic ions will be described.
David J. Wineland is an American physicist at the National Institute of Standards and Technology (NIST) physics labo- ratory in Boulder. His work has included advances in optics, specifically laser cooling of ions in Paul traps and use of trapped ions to implement quantum computing operations. Wineland received his bachelor’s degree from the University of California, Berkeley in 1965 and his PhD in 1970 working under Norman Ramsey at Harvard University. He then worked as a postdoc in Hans Dehmelt’s group at the University of Washington before joining the National Bureau of Standards in 1975 where he started the ion storage group, now at NIST, Boulder. Wineland is a fellow of the American Physical society, the American Optical society, and was elected to the National Academy of Sciences in 1992. He was the recipient of the 1990 Davisson-Germer Prize in Atomic or Surface Physics, the 1990 William F. Meggers Award of the Optical Society of America, the 1996 Einstein Medal for Laser Science of the Society of Optical and Quantum electronics, the 1998 Rabi Award from the IEEE Ultrasonics, Ferroelectrics, and Frequency Control Society, the 2001 Arthur L. Schawlow Prize in Laser. He is an American No- bel-Prize-winning physicist at the National Institute of Standards and Technology (NIST) physics laboratory. His work has included advances in optics, specifically laser cooling of ions in Paul traps and use of trapped ions to implement quantum computing operations. He was awarded the 2012 Nobel Prize in Physics, jointly with Serge Haroche, for “ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems.