Efficient estimation of multipartite quantum coherence
| Autor: | He Lu, Ting Zhang, Xiao Yuan, Xiao-Xu Fang, Qi-Ming Ding |
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| Rok vydání: | 2020 |
| Předmět: | |
| DOI: | 10.48550/arxiv.2010.02612 |
| Popis: | Quantification of coherence lies at the heart of quantum information processing and fundamental physics. Exact evaluation of coherence measures generally needs a full reconstruction of the density matrix, which becomes intractable for large-scale multipartite systems. Here, we propose a systematic theoretical approach to efficiently estimating lower and upper bounds of coherence in multipartite states. Under the stabilizer formalism, the lower bound is determined by the spectrum estimation method with a small number of measurements and the upper bound is determined by a single measurement. We verify our theory with a four-qubit optical quantum system.We experimentally implement various multi-qubit entangled states, including the Greenberger-Horne-Zeilinger state, the cluster state, and the W state, and show how their coherence are efficiently inferred from measuring few observables. Comment: 13 pages, 8 figures. Comments are welcome |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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