This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
Dynamical decoupling (DD) is a promising approach to mitigate the detrimental effects that interactions with the environment have on a quantum system. In DD, the finite-dimensional system is rotated about specified axes using strong and fast controls that eliminate system-environment interactions and protect the system fromdecoherence. In this thesis, the…
Dynamical decoupling (DD) is a promising approach to mitigate the detrimental effects that interactions with the environment have on a quantum system. In DD, the finite-dimensional system is rotated about specified axes using strong and fast controls that eliminate system-environment interactions and protect the system fromdecoherence. In this thesis, the framework of DD is theoretically studied, and later it discusses how this framework can be implemented on an infinite-dimensional system that amplifies system components rather than suppressing them through quadrature squeezing operations. It begins by studying the impact of system-environment interactions on a quantum system, and then it analyzes how DD suppresses these interactions. The conditions for protecting a finite-dimensional system through DD are reviewed, and a numerical analysis of the DD conditions for simple systems is conducted. Using bang-bang controls, a framework for decoupling decoherence-inducing components from a general finite-dimensional system is studied. Later, following an overview of schemes that amplify the strength of a quantum signal through reversible
squeezing, a theoretical study of Hamiltonian Amplification (HA) for quantum harmonic oscillators is presented. By implementing the DD framework with squeezing operations, HA achieves speed-up in the dynamics of quantum harmonic oscillators, which translates into the strengthening of interactions between harmonic oscillators. Finally, the application of HA in amplifying the third-order nonlinearity in a Kerr medium is proposed to obtain a speed-up in the implementation of controlled phase gates for optical quantum computations. Numerically simulated results show that large amplification in nonlinearity is feasible with sufficient squeezing resources, completing the set of universal quantum gates in optical quantum computing.
