I am a Sherman Fairchild postdoctoral fellow in the Walter Burke Institute for Theoretical Physics at Caltech, supervised by John Preskill.

I received my Ph.D. in Quantum Science and Engineering from the University of Chicago in 2024, advised by Liang Jiang. My thesis is Towards Practical Fault-Tolerant Quantum Computing. I obtained my B.S. in Physics from Nanjing University in 2019.

My research focuses on quantum error correction and fault-tolerant quantum computing. I am interested in designing new quantum error-correcting codes and fault-tolerant schemes that minimize space-time overhead. Additionally, I explore methods to develop noise-robust quantum processors by integrating techniques from quantum error correction, quantum control, reservoir engineering, etc. Please find my research topics and publications below.

Low-overhead fault-tolerant quantum computing with quantum low-density-parity-check (qLDPC) codes

[1]. Constant-Overhead Fault-Tolerant Quantum Computation with Reconfigurable Atom Arrays.
Q. X., J. Pablo Bonilla Ataides, Christopher A. Pattison, Nithin Raveendran, Dolev Bluvstein, Jonathan Wurtz, Bane Vasic, Mikhail D. Lukin, Liang Jiang, and Hengyun Zhou.
Nat. Phys. (2024). [QIP 2024]. [QEC 23].[Article by Quanta Magzine].

[2]. Fast and Parallelizable Logical Computation with Homological Product Codes.
Q. X., Hengyun Zhou, Guo Zheng, Dolev Bluvstein, J. Pablo Bonilla Ataides, Mikhail D. Lukin, Liang Jiang.
arXiv 2407.18490 (2024).

Hardware-efficient fault tolerance with bosonic qubits

[1]. Fault-Tolerant Operation of Bosonic Qubits with Discrete-Variable Ancillae.
Q. X., Pei Zeng, Daohong Xu, and Liang Jiang.
Phys. Rev. X (2024). [QEC 23].

[2]. Autonomous quantum error correction and fault-tolerant quantum computation with squeezed cat qubits.
Q. X., Guo Zheng, Yu-Xin Wang, Peter Zoller, Aashish A. Clerk, and Liang Jiang.
npj Quantum Inf (2023).

[3]. Construction of Bias-preserving Operations for Pair-cat Code.
Ming Yuan, Q. X., and Liang Jiang.
Phys. Rev. A (2022).

[4]. Quantum Capacity and Codes for the Bosonic Loss-Dephasing Channel.
Peter Leviant, Q. X., Liang Jiang, and Serge Rosenblum.
Quantum (2022).

[5]. Stabilizing a Bosonic Qubit Using Colored Dissipation.
Harald Putterman, Joseph Iverson, Q. X., Liang Jiang, Oskar Painter, Fernando G.S.L. Brando, and Kyungjoo Noh.
Phys. Rev. Lett. (2022). [US Patent].

[6]. Engineering Kerr-Cat Qubits for Hardware-Efficient Quantum Error Correction.
Q. X., Harald Putterman, Joseph Iverson, Kyungjoo Noh, Oskar Painter, Fernando G.S.L. Brando, and Liang Jiang.
Quantum Computing, Communication, and Simulation II. Vol. 12015. SPIE (2022).

[7]. Engineering Fast Bias-Preserving Gates on Stabilized Cat Qubits.
Q. X., Joseph Iverson, Fernando G.S.L. Brando, and Liang Jiang.
Phys. Rev. Research (2022). [US Patent].

[8]. Quantum Repeaters Based on Concatenated Bosonic and Discrete-Variable Quantum Codes.
Filip Rozpędek, Kyungjoo Noh, Q. X., Saikat Guha, and Liang Jiang.
npj Quantum Information (2021).

Tailored topological codes

Distributed Quantum Error Correction for Chip-Level Catastrophic Errors.
[1]. Q. X., Alireza Seif, Haoxiong Yan, Nam Mannucci, Bernard Ousmane Sane, Rodney Van Meter, Andrew N. Cleland, and Liang Jiang.\
Phys. Rev. Lett. (2022).

Tailored XZZX Codes for Biased Noise.
[2]. Q. X., Nam Mannucci, Alireza Seif, Aleksander Kubica, Steven T. Flammia, and Liang Jiang.
Phys. Rev. Research (2022).