In this work we consider a bipartite system consisting of magnetic dipoles, initially characterized by product-states uncorrelated until the dynamics of evolution is established by magnetic dipole interaction. We reproduce the dynamic behavior of the entanglement produced by the magnetic dipole interaction through its temporal dependence, connection with local quantum coherences or symmetries of initial states and interaction parameters, thus establishing criteria that extremize the entanglement. We also investigated the entanglement production capacity of the magnetic dipole interaction for some classes of states with lower purities, with and without initial entanglement, thus identifying relevant aspects between purity, symmetry and necessary local quantum coherences. We show, above all, that some classes of partially entangled states can preserve or generate maximum entanglement under magnetic dipole interaction for different instants of time.In this work we consider a bipartite system consisting of magnetic dipoles, initially characterized by product-states uncorrelated until the dynamics of evolution is established by magnetic dipole interaction. We reproduce the dynamic behavior of the entanglement produced by the magnetic dipole interaction through its temporal dependence, connection with local quantum coherences or symmetries of initial states and interaction parameters, thus establishing criteria that extremize the entanglement. We also investigated the entanglement production capacity of the magnetic dipole interaction for some classes of states with lower purities, with and without initial entanglement, thus identifying relevant aspects between purity, symmetry and necessary local quantum coherences. We show, above all, that some classes of partially entangled states can preserve or generate maximum entanglement under magnetic dipole interaction for different instants of time.

Aug 6, 20180 citations

Quantum Entanglement in Quasi-Equilibrium States in the Multipulse Spin Locking of the Nuclear Magnetic Resonance

G. A. Bochkin, Sergey G. Vasil’ev, E. I. Kuznetsova +1 more

Quantum entanglement is studied NMR multipulse spin locking, when a system of spins coupled by the dipole–dipole interaction in a strong magnetic field is irradiated by a sequence of resonant high-frequency $\varphi$ -pulses with the same time delay $2\tau$ between successive pulses. For times $t \sim {{T}_{2}}$ ( ${{T}_{2}} \approx \omega _{{{\text{loc}}}}^{{ - 1}}$ , ${{\omega }_{{{\text{loc}}}}}$ is determined by the dipole–dipole interaction), quasi-equilibrium with a structure depending on the relation between the pulsed field ${{\omega }_{1}} = \varphi {\text{/}}2\tau$ and ${{\omega }_{{{\text{loc}}}}}$ is established in the system. For ${{\omega }_{1}} \lessapprox {{\omega }_{{{\text{loc}}}}}$ , a one-temperature quasi-equilibrium state arises, while a quasi-equilibrium with the dipole and Zeeman temperatures appears for ${{\omega }_{1}} \gg {{\omega }_{{{\text{loc}}}}}$ . The temperature dependence of entanglement is investigated for ${{\omega }_{1}} \lessapprox {{\omega }_{{{\text{loc}}}}}$ . For ${{\omega }_{1}} \gg {{\omega }_{{{\text{loc}}}}}$ , the further evolution of the system is determined by the Provotorov equations and leads to the equalization of the dipole and Zeeman temperatures. It is shown that the entanglement is absent in this case.Quantum entanglement is studied NMR multipulse spin locking, when a system of spins coupled by the dipole–dipole interaction in a strong magnetic field is irradiated by a sequence of resonant high-frequency $$\varphi $$ -pulses with the same time delay $$2\tau $$ between successive pulses. For times $$t \sim {{T}_{2}}$$ ( $${{T}_{2}} \approx \omega _{{{\text{loc}}}}^{{ - 1}}$$ , $${{\omega }_{{{\text{loc}}}}}$$ is determined by the dipole–dipole interaction), quasi-equilibrium with a structure depending on the relation between the pulsed field $${{\omega }_{1}} = \varphi {\text{/}}2\tau $$ and $${{\omega }_{{{\text{loc}}}}}$$ is established in the system. For $${{\omega }_{1}} \lessapprox {{\omega }_{{{\text{loc}}}}}$$ , a one-temperature quasi-equilibrium state arises, while a quasi-equilibrium with the dipole and Zeeman temperatures appears for $${{\omega }_{1}} \gg {{\omega }_{{{\text{loc}}}}}$$ . The temperature dependence of entanglement is investigated for $${{\omega }_{1}} \lessapprox {{\omega }_{{{\text{loc}}}}}$$ . For $${{\omega }_{1}} \gg {{\omega }_{{{\text{loc}}}}}$$ , the further evolution of the system is determined by the Provotorov equations and leads to the equalization of the dipole and Zeeman temperatures. It is shown that the entanglement is absent in this case.

Journal of Experimental and Theoretical Physics LettersApr 1, 20251 citation

Quantum Entanglement and Magnetic Polarity

Prithvi Pandey

Jan 1, 20250 citations

Entanglement of Magnetically Levitated Massive Schrödinger Cat States by Induced Dipole Interaction

Ryan J. Marshman, Sougato Bose, Andrew A. Geraci +1 more

Quantum entanglement provides a novel way to test short-distance quantum physics in a non-relativistic regime. We provide entanglement-based protocols to potentially test the magnetically induced dipole-dipole interaction and the Casimir-Polder potential between the two nano-crystals kept in a Schrodinger Cat state. Our scheme is based on the Stern-Gerlach (SG) apparatus, where we can witness the entanglement mediated by these interactions for the nano-crystal mass m~10^-19 kg with a spatial superposition size of order 0.1 micron in a trap relying on diamagnetic levitation. We show that it is possible to close the SG interferometer in position and momentum with a modest gradient in the magnetic field.Quantum entanglement provides a novel way to test short-distance quantum physics in a non-relativistic regime. We provide entanglement-based protocols to potentially test the magnetically induced dipole-dipole interaction and the Casimir-Polder potential between the two nano-crystals kept in a Schrodinger Cat state. Our scheme is based on the Stern-Gerlach (SG) apparatus, where we can witness the entanglement mediated by these interactions for the nano-crystal mass m~10^-19 kg with a spatial superposition size of order 0.1 micron in a trap relying on diamagnetic levitation. We show that it is possible to close the SG interferometer in position and momentum with a modest gradient in the magnetic field.

arXiv:2304.14638Apr 28, 20230 citations

Entangled States in Macroscopic Paramagnetic Systems

V. I. Tsifrinovich, G. P. Berman, G. D. Doolen +1 more

APSMar 1, 19980 citations

\varphi

-pulses with the same time delay

2\tau

between successive pulses. For times

t \sim {{T}_{2}}

(

{{T}_{2}} \approx \omega _{{{\text{loc}}}}^{{ - 1}}

{{\omega }_{{{\text{loc}}}}}

is determined by the dipole–dipole interaction), quasi-equilibrium with a structure depending on the relation between the pulsed field

{{\omega }_{1}} = \varphi {\text{/}}2\tau

and

{{\omega }_{{{\text{loc}}}}}

is established in the system. For

{{\omega }_{1}} \lessapprox {{\omega }_{{{\text{loc}}}}}

, a one-temperature quasi-equilibrium state arises, while a quasi-equilibrium with the dipole and Zeeman temperatures appears for

{{\omega }_{1}} \gg {{\omega }_{{{\text{loc}}}}}

. The temperature dependence of entanglement is investigated for

{{\omega }_{1}} \lessapprox {{\omega }_{{{\text{loc}}}}}

. For

{{\omega }_{1}} \gg {{\omega }_{{{\text{loc}}}}}

, the further evolution of the system is determined by the Provotorov equations and leads to the equalization of the dipole and Zeeman temperatures. It is shown that the entanglement is absent in this case.