Exploration of Single-Spin Control in Strained Bi2WO6 for Quantum Computing Applications
Zachary L. Clemens, Nabaraj Pokhrel, Sriram P. Ramkumar, PhD, and Elizabeth A. Nowadnick, PhD
Department of Materials Science and Engineering, University of California, Merced
Most quantum computers utilize quantum bits or qubits which function as the quantum analogue of a classical bit. These qubits act in accordance with quantum properties existing in a superposition of two quantum states, 0 and 1. Currently, several physical realizations of qubits are under active exploration including semiconductor quantum dots, and superconducting Josephson junctions. Ferroelectric materials doped with magnetic impurities offer an alternative platform that could enable electric field-control of the qubit state. Existing research has indicated that careful optimization of these ferroelectric switching pathways can lower the total energy required to reverse the polarization and therefore the coupled spin. Here, we investigate the ferroelectric aurivillius-phase layered perovskite Bi2WO6 doped with Fe3+ magnetic impurities. Bi2WO6 crystallizes in a low-symmetry orthorhombic structure, indicating that the local crystallographic environment may make it energetically favorable for the spin to point along a specific axis. We began our analysis starting from a high symmetry paraelectric structure with induced structural distortions and perform first-principles calculations on resultant phases to identify the ground state which is ferroelectric. We continued by identifying the stability of Bi2WO6phases as a function of strain for the purposes of thin film growth in the presence of lattice mismatch and indicate the most promising phase and potential path intermediates for future quantum research applications.