Entanglement measures induced by fidelity-based distances

Zhihao Ma, Fulin Zhang, Jing‐Ling Chen

Mostafizur Rahaman Laskar

We propose a quantum distance measure between probability distributions encoded in quantum states based on the fragility of quantum interference under entangling evolution. The Quantum Interference-Induced Bhattacharyya Distance (QIBD) is defined through a single-ancilla interferometric circuit in which an interaction Hamiltonian generates correlation-dependent phases that modulate interference visibility. When the interaction vanishes, QIBD reduces to the classical Bhattacharyya distance; however, for entangling interactions, it cannot be expressed as a function of fidelity alone. Numerical simulations demonstrate that QIBD responds to correlation structure in ways that overlap-based measures do not, suggesting potential utility in contexts where interaction-aligned correlations are physically relevant.

Vahid Azimi Mousolou

Radim Filip

A feasible device for measurement of fidelity, overlap, purity, and Hilbert-Schmidt distance of two mixed states is proposed. In addition, this device realizes a decomposable entanglement witness-measurement for bipartite systems, corresponding to Werner criterion of entanglement. The measurement, based on interferometric setup and the control-phase gate, can be directly implemented in the cavity quantum electrodynamics, trapped ion, and electromagnetically induced transparency experiments.

Shunlong Luo

P. K. Aravind