Engineering Quantum Frontiers: Noise, Devices, and Scalable Architectures for Semiconductor Quantum Technologies

Abstract:
Quantum technologies offer transformative opportunities in computing, communication, and
sensing. However, their realization is fundamentally constrained by materials imperfections,
device-level noise, and scalability challenges. In this seminar, I will present my research on
engineering solid-state quantum devices, with a focus on semiconductor spin qubit platforms.
I will first discuss recent advances in semiconductor spin qubit devices, where charge noise
from microscopic two-level fluctuators remains a dominant limitation to coherence of qubits.
By developing tools for noise source characterization and proposing experimentally feasible
mitigation strategies, this work provides practical pathways toward more robust
semiconductor quantum devices.
I will then introduce quantum emitters in silicon as scalable building blocks for quantum
networks, highlighting protocols for deterministic photonic graph-state generation and spinphoton
interfaces. I will also present a scheme for entangling gates between distant spin
qubits that are useful for scalable, modular architectures.
Finally, I will conclude by outlining a forward-looking research and teaching vision,
emphasizing interdisciplinary collaboration in quantum materials, devices, and emerging
quantum technologies.
(4) Bio:
Yujun Choi is a Postdoctoral Associate in the Department of Physics at Virginia Tech. He
received his B.S. and M.S. in Physics from Yonsei University, and Ph.D. in Physics from
University of Wisconsin-Madison. His research focuses on semiconductor spin qubit devices
for quantum computing and quantum networks, with an emphasis on characterization and
mitigation of noise, decoherence and open quantum systems, and scalable architectures. His
work has been published in journals including Physical Review Letters, npj Quantum
Information, Physical Review A, and so on.