Composite Pulse Sequences For Ion Trap Quantum Computation

The control of quantum systems is limited by unwanted interactions with the environment and uncertainties in the applied control fields. For ions these uncertainties include unwanted fluctuations in the intensity and the frequency of the electromagnetic field used to control the qubit. For unknown static errors on the time scale of the experiment, compensating composite pulses sequences can be used to minimize the effect of these errors. In this talk, I will describe the general method of compensating composite pulse sequences for single qubit and multi-qubit systems. I will then present experimental results showing how these sequences can compensate for inhomogeneous control, reduce cross-talk between components, and improve total gate fidelity. I will conclude by showing how these methods can be extended to suppress errors that fluctuate in time.

Professor Brown is an Associate Professor in the Schools of Chemistry and Biochemistry, Computational Science and Engineering, and Physics at the Georgia Institute of Technology. He was a Hertz fellow at UC Berkeley where he received his PhD in 2003. He was then a postdoctoral fellow at MIT before starting at Georgia Tech in 2007. His group studies experimental and theoretical challenges to building scalable quantum computers and the application of quantum information techniques to the study of cold molecules. He currently serves as the Vice-Chair of the Topical Group for Quantum Information of the American Physical Society.