activity
20242026
collaborators

6 papers

quant-ph2026

Rank and Range Criteria for Mixed-State Determination from Local Marginals

Xinyu Qiu, Minglong Qin, Caohan Cheng +2

Determining whether a mixed quantum state is uniquely determined among all states by its k-body marginals (k-UDA) is a fundamental problem in quantum system certification. We devel…

quant-ph2026

Mixed States Uniquely Determined by Marginals and Additivity

Xinyu Qiu, Lin Chen, Genwei Li +1

Identifying whether a mixed quantum state is uniquely determined among all states (UDA) by its local marginals is a basic problem in quantum information theory. We establish necess…

math.OC2025

Regularization of Port-Hamiltonian Descriptor Systems

Delin Chu, Volker Mehrmann

We study the regularization problem for port-Hamiltonian descriptor systems by proportional and/or derivative output feedback. Necessary and sufficient conditions are given, which…

math.OC2024

Asymptotic Stability and Strict Passivity of Port-Hamiltonian Descriptor Systems via State Feedback

Delin Chu, Volker Mehrmann

While port-Hamiltonian descriptor systems are known to be stable and passive, they may not be asymptotically stable or strictly passive. Necessary and sufficient conditions are pre…

math.OC2024

Stabilization of linear Port-Hamiltonian Descriptor Systems via Output Feedback

Delin Chu, Volker Mehrmann

The structure preserving stabilization of (possibly non-regular) linear port-Hamiltonian descriptor (pHDAE) systems by output feedback is discussed. For general descriptor systems…

math.OC2024

Port-Hamiltonian Realizations of Positive Real Descriptor Systems

Delin Chu, Volker Mehrmann

The relationship between port-Hamiltonian and positive real descriptor systems is investigated. It is well-known that port-Hamiltonian systems are positive real, but the converse i…