Author ORCID Identifier
0000-0003-4836-1246
Defense Date
2026
Document Type
Dissertation
Degree Name
Doctor of Philosophy
Department
Mechanical and Nuclear Engineering
First Advisor
Jayasimha Atulasimha
Abstract
Conventional CMOS scaling has driven remarkable advances in computing but faces increasing physical and energy constraints, motivating alternative computing paradigms that integrate memory and computation while improving energy efficiency. Nanoscale magnetic systems offer a promising platform for such approaches because their intrinsic nonlinear dynamics and localized magnetic fields can support both classical and quantum information processing. This thesis investigates nanomagnetic systems for physical reservoir computing and, with primary emphasis, for localized quantum control of spin qubits.
The first part explores dipole-coupled nanomagnet arrays as physical reservoirs. Micromagnetic simulations demonstrate nonlinear dynamical behavior with high short-term memory and parity-check capacity, enabling accurate classification and time-series prediction. A single nanomagnetic reservoir can perform multiple tasks by training only the output layer through linear regression, demonstrating a versatile and robust computing architecture tolerant to thermal noise and fabrication variations.
The second and primary focus of this thesis is nanoscale magnetic control of quantum spins. We theoretically investigate nanomagnets and skyrmions as localized microwave sources for high-fidelity single-qubit gates. Simulations demonstrate gate fidelities exceeding 99.9% while substantially reducing magnetic cross-talk between neighboring qubits compared with conventional microwave antennas. Experimentally, we demonstrate coherent control of a nitrogen-vacancy (NV) center in diamond using microwave magnetic fields generated by a nanoscale magnet driven by surface acoustic waves in lithium niobate. The device produces spatially localized oscillating fields and enables high-contrast Rabi oscillations with controllable Rabi frequencies through input power. These results establish nanoscale magnetic systems as a scalable pathway toward energy-efficient, spatially selective quantum control and provide a bridge between classical and quantum computing.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
7-27-2026
Included in
Computer and Systems Architecture Commons, Electrical and Electronics Commons, Electromagnetics and Photonics Commons, Electronic Devices and Semiconductor Manufacturing Commons, Hardware Systems Commons, Nanoscience and Nanotechnology Commons, Nanotechnology Fabrication Commons, Semiconductor and Optical Materials Commons