9 papers
Estimating the concurrence for quantum states via symmetric measurements
Hao-Fan Wang, Wen Zhou, Lin Chen +1
We derive improved lower bounds of concurrence induced by symmetric measurements, which retains experimental feasibility without state tomography. More importantly, we resolve a re…
Non-Perturbative Geometric Framework for Single-Qubit Gates under Always-On Couplings
Junkai Zeng, Lin Chen, Xiu-Hao Deng
In qubit arrays with always-on couplings, single-qubit gates pose a control challenge often as demanding as entangling operations. The same interactions that enable two-qubit entan…
Entanglement distillation on symmetric two-qutrit entangled states of rank five
Zihua Song, Lin Chen, Yongge Wang
Entanglement distillation is a key step in quantum information, both theoretically and practically. It has been proven that non-positive-partial transpose (NPT) entangled states of…
Virtual Quantum Markov Chain of four-qubit systems
Zhixing Chen, Lin Chen
We extend the framework of virtual quantum Markov chains (VQMCs) from tripartite systems to the four-qubit setting. Structural criteria such as the kernel-inclusion condition are a…
Spectral characterizations of entanglement witnesses
Zhiwei Song, Lin Chen
We present a systematic investigation of the spectral properties of entanglement witnesses (EWs). Specifically, we analyze the infimum and supremum of the largest eigenvalue, the s…
Equality condition for a matrix inequality by partial transpose
Nalan Wang, Lin Chen
The partial transpose map is a linear map widely used quantum information theory. We study the equality condition for a matrix inequality generated by partial transpose, namely $\r…