Chotorlishvili L., Gudyma A., Wätzel J., Ernst A., and Berakdar J.

The concept of quantum memory plays an incisive role in the quantum information theory. As confirmedby the several recent rigorous mathematical studies, the quantum memory inmate in the bipartite systemρABcan reduce the uncertainty about partB, after measurements done on partA. In the present work, we extendthis concept to systems with a spin-orbit coupling and introduce the notion of spin-orbit quantum memory.We self-consistently explore the Uhlmann fidelity, the pre- and the post-measurement entanglement entropy,and the post-measurement conditional quantum entropy of the system with spin-orbit coupling and show thatmeasurement performed on the spin subsystem decreases the uncertainty of the orbital part. The uncoveredeffect enhances with the strength of the spin-orbit coupling. We study the concept of macroscopic realismintroduced by Leggett and Garg [Phys.Rev.Lett.54,857(1985)] and observe that POVM measurements doneon the system under the particular protocol are noninvasive. For the extended system, we perform quantumMonte Carlo calculations and consider the reshuffling of the electron densities due to an external electric field

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