Related Experiment Video
Updated: Aug 6, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Direct characterization of quantum dynamics via generalized weak values
1National Laboratory of Solid State Microstructures, Key Laboratory of Intelligent Optical Sensing and Manipulation, and Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Sciences and School of Physics, Jiangsu Physical Science Research Center, Nanjing University, Nanjing 210093, China.
Science Advances
|July 17, 2026
Summary
Process weak values (PWVs) capture quantum system evolution, unlike conventional weak values. This new method efficiently characterizes quantum processes, including unitary and non-Hermitian ones, with reduced experimental complexity.
Area of Science:
- Quantum Information Science
- Quantum Measurement Theory
- Quantum Process Characterization
Background:
- Weak values, derived from weak measurements, offer complex-valued insights into quantum systems.
- Conventional weak values lack the ability to incorporate system dynamics between measurements.
- Characterizing quantum processes typically requires complex quantum process tomography.
Purpose of the Study:
- To introduce a novel theoretical framework, the process weak value (PWV), to include quantum evolution.
- To enable direct characterization of quantum processes by linking PWVs to unitary operator matrix elements.
- To experimentally validate the PWV formalism for various quantum processes.
Main Methods:
- Development of the process weak value (PWV) formalism incorporating quantum evolution.
- Establishing a theoretical connection between PWVs and the matrix elements of unitary operators.
- Experimental implementation and validation using single-photon, two-photon, and parity-time symmetric quantum processes.
Main Results:
- Demonstrated the capability of PWVs to characterize quantum system evolution.
- Successfully validated the PWV formalism experimentally on diverse quantum processes.
- PWV method shows reduced basis requirements and avoids complex reconstruction compared to quantum process tomography.
Conclusions:
- The process weak value formalism provides a powerful tool for direct quantum process characterization.
- PWVs enhance efficiency and scalability for analyzing quantum dynamics.
- This formalism opens new avenues for foundational studies in weak measurements and quantum process analysis.
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