Modeling, analysis and control of quantum electronic devices
Abstract
This dissertation focuses on two connected areas: quantum computation and quantum
control. Two proposals to construct a quantum computer, using nuclear magnetic
resonance (NMR) and superconductivity, are introduced. We give details about the
modeling, qubit realization, one and two qubit gates and measurement in the language
that mathematicians can understand and fill gaps in the original literatures. Two
experimental examples using liquid NMR are also presented. Then we proceed to
investigate an example of quantum control, that of a magnetometer using quantum
feedback. Previous research has shown that feedback makes the measurement robust
to an unknown parameter, the number of atoms involved, with the assumption that
the feedback is noise free. To evaluate the effect of the feedback noise, we extend the
original model by an input noise term. We then compute the steady state performance
of the Kalman filter for both the closed-loop and open-loop cases and retrieve the
estimation error variances. The results are compared and criteria for evaluating the
effects of input noise are obtained. Computations and simulations show that the
level of input noise affects the measurement by changing the region where closed loop
feedback is beneficial.
Citation
Zhang, Zhigang (2006). Modeling, analysis and control of quantum electronic devices. Doctoral dissertation, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1811.