03/30/2026
By Ipsita Sinha
The Kennedy College of Science, Department of Physics and Applied Physics, invites you to attend a Master's Thesis defense by Ipsita Sinha on: " Identifying sources of single-qubit crosstalk errors in a three-body tunable superconducting architecture."
Date: April 10, 2026
Time: 3 - 5 p.m.
Location: Olney 136, Physics Conference Room
Committee:
- Hugo Ribeiro, Assistant Professor, Department of Physics and Applied Physics, University of Massachusetts Lowell. (Faculty Advisor)
- Shiwen Zhang, Ph.D., Assistant Professor, Department of Mathematics and Statistics, University of Massachusetts Lowell. (Faculty Advisor)
- Viktor A Podolskiy ,Ph.D., Professor, Department of Physics and Applied Physics, University of Massachusetts Lowell
Abstract:
Over the years, the fabrication and control of a qubit have been widely investigated. Generation of high fidelity (quality) single qubit gate is done routinely in lab with very little error. However, for successful operation of a fault tolerant quantum computer, one needs multiple such qubits. Controlling and isolating qubits during gate operation in a multi-qubit system is very challenging. When the qubits are fabricated on a single chip, the interactions between them result in unwanted coupling during a single qubit gate operation. These unwanted couplings come from crosstalk phenomena, which lead to crosstalk errors that limit the quality of gates.
In this thesis, I have considered a tunable three-body transmon architecture (two data qubits and one coupler) and investigated the origin of crosstalk errors when driving single-qubit gates and the system is tuned to the idling regime (where the data qubits are effectively decoupled). Our results show that even when the effective coupling is turned off, a residual quantum interaction between the data qubits persists and is the main source of gate errors together with the usual leakage errors.