2016/04/01 by Ya-Li Yuan, Xi-Wen Hou
Computer Science · Physics and Astronomy · #Condensed matter physics #Magnetic field #Negativity effect #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum discord #Quantum entanglement #Quantum mechanics #Qubit #Qutrit #Thermal #Thermodynamics
paper · doi:10.1142/s0219749916500167
crossref issued 2016/04/01 · crossref published 2016/04/01 · crossref published-print 2016/04/01 · openalex publication_date 2016/04/01 · crossref created 2016/06/17 · crossref published-online 2016/07/13 · crossref deposited 2019/08/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/26 · crossref indexed 2026/08/03
The investigation of quantum discord has mostly focused on two-qubit systems due to the complicated minimization involved in quantum discord for high-dimensional states. In this work, three geometric discords are studied for the thermal state in a two-qutrit system with various couplings, external magnetic fields, and temperatures as well, where the entanglement measured in terms of the generalized negativity is calculated for reference. It is shown that three geometric discords are more robust against temperature and magnetic field than the entanglement negativity. However, all four quantities exhibit a similar behavior at lower temperature and weak magnetic field. Remarkably, three geometric discords at finite temperature reveal the phenomenon of double sudden changes at different magnetic fields while the negativity does not. Moreover, the hierarchy among three discords is discussed. Those adjustable discords with the varied coupling, temperature, and magnetic field are useful for the understanding of quantum correlations in high-dimensional states and quantum information processing.