Publications
Research Papers
Listed by release date
Near-optimal incoherent tomography of low-rank quantum channels
Kean Chen, Aadil Oufkir
Manuscript
Released: 2026-09 · [pdf] · [arXiv]AI use disclosure
The upper-bound proof for channels with gapped Choi spectrum was developed by the human authors. After being provided with this proof as context, GPT-6 Astra generated the proof strategy for the general upper bound. GPT-5.6 Sol generated the lower-bound proof after being provided with the earlier construction from [CGO+26] and the suggestion to pursue a van Trees-type argument. The new hard family of channels used in the lower bound was generated by GPT-6 Astra. The authors subsequently checked, revised, and completed all AI-generated arguments and take full responsibility for the correctness and presentation of the results.
Quantisation of Abstract Data Types
Mingsheng Ying, Zhicheng Zhang, Kean Chen
Manuscript
Released: 2026-09 · [pdf] · [arXiv]Nearly Sample-Optimal Estimators for Quantum Rényi and Tsallis Entropies
Kean Chen, Qisheng Wang
Manuscript
Released: 2026-08 · [pdf] · [arXiv]AI use disclosure
The authors used Large Language Models as AI-assisted research and writing tools throughout the preparation of this paper. The tools were used to help brainstorm ideas and explore proof strategies. Portions of the paper text were redrafted or modified with AI assistance across all sections. All final mathematical claims, algorithms, proofs, citations, and wording were reviewed, edited, and validated by the authors. The authors assume responsibility for all content of the paper.
Quantum Multi-Level Estimation of Functionals of Discrete Distributions
Kean Chen, Minbo Gao, Tongyang Li, Qisheng Wang, Xinzhao Wang
ICALP 2026
Released: 2026-05 · [pdf] · [arXiv]Strict Hierarchy for Quantum Channel Certification to Unitary
Kean Chen, Qisheng Wang, Zhicheng Zhang
ICALP 2026
Released: 2026-04 · [pdf] · [arXiv]Quantum channel tomography: optimal bounds and a Heisenberg-to-classical phase transition
Kean Chen, Filippo Girardi, Aadil Oufkir, Nengkun Yu, Zhicheng Zhang
FOCS 2026
Released: 2026-04 · [pdf] · [arXiv]
This paper subsumes prior preprints arXiv:2512.13614 (2025), arXiv:2601.04180 (2026), arXiv:2601.10683 (2026)Trace Estimation of Quantum State Powers: Sample Complexity and Computational Hardness
Kean Chen, Yupan Liu, Qisheng Wang
Manuscript
Released: 2026-04 · [pdf] · [arXiv]
This paper extends the prior COLT 2025 paper arXiv:2505.09563v1 (2025)TopoLS: Lattice Surgery Compilation via Topological Program Transformations
Junyu Zhou, Yuhao Liu, Ethan Decker, Justin Kalloor, Mathias Weiden, Kean Chen, Costin Iancu, Gushu Li
POPL 2027
Released: 2026-01 · [pdf] · [arXiv]AlphaSyndrome: Tackling the Syndrome Measurement Circuit Scheduling Problem for QEC Codes
Yuhao Liu, Shuohao Ping, Junyu Zhou, Ethan Decker, Justin Kalloor, Mathias Weiden, Kean Chen, Yunong Shi, Ali Javadi-Abhari, Costin Iancu, Gushu Li
ASPLOS 2026
Released: 2026-01 · [pdf] · [arXiv]Optimal lower bound for quantum channel tomography in away-from-boundary regime
Kean Chen, Zhicheng Zhang, Nengkun Yu
Appearing in FOCS 2026 as the merged paper arXiv:2604.17369 (2026)
Released: 2026-01 · [pdf] · [arXiv]Quantum channel tomography and estimation by local test
Kean Chen, Nengkun Yu, Zhicheng Zhang
Appearing in FOCS 2026 as the merged paper arXiv:2604.17369 (2026)
Released: 2025-12 · [pdf] · [arXiv]A List of Complexity Bounds for Property Testing by Quantum Sample-to-Query Lifting
Kean Chen, Qisheng Wang, Zhicheng Zhang
Manuscript
Released: 2025-12 · [pdf] · [arXiv]Inverse-free quantum state estimation with Heisenberg scaling
Kean Chen
Manuscript
Released: 2025-10 · [pdf] · [arXiv]Approximation does not help in quantum unitary time-reversal
Kean Chen, Nengkun Yu, Zhicheng Zhang
STOC 2026
Released: 2025-07 · [pdf] · [arXiv]Simultaneous Estimation of Nonlinear Functionals of a Quantum State
Kean Chen, Qisheng Wang, Zhan Yu, Zhicheng Zhang
IEEE Transactions on Information Theory (T-IT), 2026 & AQIS 2025
Released: 2025-05 · [pdf] · [arXiv]Improved Sample Upper and Lower Bounds for Trace Estimation of Quantum State Powers
Kean Chen, Qisheng Wang
COLT 2025
Released: 2025-05 · [pdf] · [arXiv]Verifying Fault-Tolerance of Quantum Error Correction Codes
Kean Chen, Yuhao Liu, Wang Fang, Jennifer Paykin, Xin-Chuan Wu, Albert Schmitz, Steve Zdancewic, Gushu Li
CAV 2025
Released: 2025-01 · [pdf] · [arXiv]Local Test for Unitarily Invariant Properties of Bipartite Quantum States
Kean Chen, Qisheng Wang, Zhicheng Zhang
IEEE Transactions on Information Theory (T-IT), 2026
Released: 2024-04 · [pdf] · [arXiv]Spatio-Temporal Point Process for Multiple Object Tracking
Tao Wang, Kean Chen, Weiyao Lin, John See, Zenghui Zhang, Qian Xu, Xia Jia
IEEE Transactions on Neural Networks and Learning Systems (TNNLS), 2023
Released: 2023-02 · [pdf] · [arXiv]Unitarity Estimation for Quantum Channels
Kean Chen, Qisheng Wang, Peixun Long, Mingsheng Ying
IEEE Transactions on Information Theory (T-IT), 2023
Released: 2022-12 · [pdf] · [arXiv]VeriQBench: A Benchmark for Multiple Types of Quantum Circuits
Kean Chen, Wang Fang, Ji Guan, Xin Hong, Mingyu Huang, Junyi Liu, Qisheng Wang, Mingsheng Ying
Manuscript
Released: 2022-06 · [pdf] · [arXiv]Automatic Test Pattern Generation for Robust Quantum Circuit Testing
Kean Chen, Mingsheng Ying
ACM Transactions on Design Automation of Electronic Systems (TODAES), 2024
Released: 2022-02 · [pdf], · [arXiv]End-to-End Video Instance Segmentation via Spatial-Temporal Graph Neural Networks
Tao Wang, Ning Xu, Kean Chen, Weiyao Lin
ICCV 2021
Released: 2021-10 · [pdf] · [arXiv]Quantum Algorithm for Fidelity Estimation
Qisheng Wang, Zhicheng Zhang, Kean Chen, Ji Guan, Wang Fang, Junyi Liu, Mingsheng Ying
IEEE Transactions on Information Theory (T-IT), 2023
Released: 2021-03 · [pdf] · [arXiv]AP-Loss for Accurate One-Stage Object Detection
Kean Chen, Weiyao Lin, Jianguo Li, John See, Ji Wang, Junni Zou
IEEE Transactions on Pattern Analysis and Machine Intelligence (T-PAMI), 2021
Released: 2020-08 · [pdf] · [arXiv]PIoU Loss: Towards Accurate Oriented Object Detection in Complex Environments
Zhiming Chen, Kean Chen, Weiyao Lin, John See, Hui Yu, Yan Ke, Cong Yang
ECCV 2020
Released: 2020-07 · [pdf] · [arXiv]Towards Accurate One-Stage Object Detection with AP-Loss
Kean Chen, Jianguo Li, Weiyao Lin, John See, Ji Wang, Lingyu Duan, Zhibo Chen, Changwei He, Junni Zou
CVPR 2019
Released: 2019-04 · [pdf], [arXiv]
Talks
Quantum Channel Tomography: Optimal Bounds and a Heisenberg-to-Classical Phase Transition
Invited talk at University of Waterloo
Presented: 2026-07Approximation Does Not Help in Quantum Unitary Time-Reversal
Contributed talk at STOC 2026
Presented: 2026-06Quantum Channel Tomography: Optimal Bounds and a Heisenberg-to-Classical Phase Transition
Invited talk at STOC 2026 Workshop on Random Purification Channel
Presented: 2026-06Approximation Does Not Help in Quantum Unitary Time-Reversal
Invited talk at The Hong Kong University of Science and Technology (Guangzhou)
Presented: 2025-07Verifying Fault-Tolerance of Quantum Error Correction Codes
Invited talk at Rutgers University
Presented: 2025-05Verifying Fault-Tolerance of Quantum Error Correction Codes
Invited talk at Tsinghua University
Presented: 2025-03