2023/01/28 by Manis Hazra, Hazra, Manis, Debabrata Goswami +1 · 2 citations
Neuroscience · Physics and Astronomy · #FOS: Physical sciences #Laser-Matter Interactions and Applications #Photoreceptor and optogenetics research #Quantum Physics (quant-ph) #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.48550/arxiv.2301.12295
openalex publication_date 2023/01/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Being the key resource in quantum physics, the proper quantification of coherence is of utmost importance. Amid complex-looking functionals in quantifying coherence, we set forth a simple and easy-to-evaluate approach: Principal diagonal difference of coherence (CPDD), which we prove to be non-negative, self-normalized, and monotonic (under any incoherent operation). To validate this theory, we thought of a fictitious two-qubit system (both interacting and non-interacting) and, through the laser pulse-system interaction (semi-classical approach), compare the coherence evolution of CPDD with the relative entropy of coherence (C_(r.e)) and l1-norm of coherence (C_(l1 )), in a pure-state regime. The numerical results show that the response of CPDD is better than the other two quantifiers. To the best of our knowledge, this letter is the first to show that a set of density-matrix diagonal elements carries complete information on the coherence (or superposition) of any pure quantum state.