Parameterized quantum comb and simpler circuits for reversing unknown qubit-unitary operations

Training formalism for the parameterized quantum comb framework.

Abstract

Quantum comb is an essential tool for characterizing complex quantum protocols in quantum information processing. In this work, we introduce PQComb, a framework leveraging parameterized quantum circuits to explore the capabilities of quantum combs for general quantum process transformation tasks and beyond. By optimizing PQComb for time-reversal simulations of unknown unitary evolutions, we develop a simpler protocol for unknown qubit unitary inversion that reduces the ancilla qubit overhead from 6 to 3 compared to the existing method in [Yoshida, Soeda, Murao, PRL 131, 120602, 2023]. This demonstrates the utility of quantum comb structures and showcases PQComb’s potential for solving complex quantum tasks. Our results pave the way for broader PQComb applications in quantum computing and quantum information, emphasizing its versatility for tackling diverse problems in quantum machine learning.

Publication
arXiv:2403.03761
Yin Mo
Yin Mo
Research Associate

I obtained my BS in Fundamental Science in Physics and Mathematics from Tsinghua University. I obtained my PhD degree in Computer Science from the University of Hong Kong. My research interests include quantum information theory, quantum supermaps and quantum machine learning.

Lei Zhang
Lei Zhang
PhD Student

I obtained my BMath in AMath, CO & joint PMath from the University of Waterloo. My research interests include quantum information theory and quantum machine learning.

Yu-Ao Chen
Yu-Ao Chen
Research Associate

I obtained my BS in Mathematics and Applied Mathematics from University of Science and Technology of China. I obtained my PhD degree in Applied Mathematics from University of Chinese Academy of Sciences under the supervision of Prof. Xiao-Shan Gao. My research interests include quantum computing, symbolic computation and cryptanalysis.

Yingjian Liu
Yingjian Liu
Research Assistant

I obtained my BS in Electronics at Shandong University, China. Then I obtained my MS degree in Optics and Photonics from Karlsruhe Institute of Technology in Germany and finished my master’s thesis at ICFO in Spain. My research interests include quantum computation, quantum information and quantum many-body physics.

Tengxiang Lin
Tengxiang Lin
Research Assistant

I obtained my B.E. in Information Engineering from South China University of Technology. My research interests include quantum information theory and quantum computation.

Xin Wang
Xin Wang
Associate Professor

The main focus of my research is to better understand the limits of information processing with quantum systems and the power of quantum artificial intelligence.