Fig. 1. Classification of entanglement and quantum discord in quantum states of separated systems^[23]

Fig. 2. Venn diagram

Fig. 3. Set of 2-qubit states with maximally mixed boundary values^[27]

Fig. 4. Quantum discord for Werner state^[13]

Fig. 5. Quantum discord of states with maximally mixed marginals^[56]

Fig. 6. Quantum state classical correlation and quantum discord function

Fig. 7. Quantum discord^[76]. (a) Werner-GHZ state; (b) Mixed state

Fig. 8. Quantum discord (solid line) and global quantum discord (dashed line)

Fig. 9. Quantum discord of the three-qubit state (dashed line) and quantum discord of the four-qubit state (solid line) under phase flip channel^[87]

Fig. 10. Remote state preparation protocol^[92]

Fig. 11. Experimental setup for implementing remote state preparation protocol^[92]

Fig. 12. Quantum teleportation^[99]. (a) ΡTEL for hybrid teleportation; (b) ΡTEL for hybrid remote-state preparation

Fig. 13. Experimental setup for simulating invisible transmission of high-dimensional quantum states or optical images using thermal light source^[107]

Fig. 14. Simulation results of high-dimensional state transmitted at single-photon level^[107]

Fig. 15. Thermal two-photon state transfer optical image ^[107]

Fig. 16. Variation of quantum discord and entanglement with temperature in quantum battery of 2-qubit system^[115]

Fig. 17. Schematic of DQC1 circuit^[136]

Fig. 18. Schematic of quantum states space ^[22]

Fig. 19. Quantum discord in DQC1 circuit^[136]