Towards qubit noise spectroscopy by quantum bang-bang control
Author(s)Chen, Zilong, 1981-
Massachusetts Institute of Technology. Dept. of Physics.
Isaac L. Chuang.
MetadataShow full item record
Quantum bang-bang control is a method of suppressing decoherence in qubits [VKL99, VL98]. To date, mathematically rigorous treatments of quantum bang-bang control offered little intuition. To complement existing approaches and to seek better understanding, I present intuitive pictures to think about quantum bang-bang control. In addition, I develop a formalism for treating phase noise moments of a qubit under quantum bang-bang control. Although the desired purpose of quantum bang-bang control is to remove noise, it is conceivable that it can be used to infer information about the noise process and coupling on a qubit. By using a simple random rotation model of single qubit dephasing, I demonstrate how quantum bang-bang control can distinguish between dephasing under different stochastic processes. I also show how quantum bang-bang control can determine noise coupling in a toy model where noise couples to the qubit via a fixed noise axis. These two demonstrations indicate the potential of quantum bang-bang control as a tool for qubit noise spectroscopy.
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, June 2004.Includes bibliographical references (p. 89-91).
DepartmentMassachusetts Institute of Technology. Dept. of Physics.
Massachusetts Institute of Technology