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arXiv · 0902.3337

Quantum Entanglement in Nitrosyl Iron Complexes

S. M. Aldoshin·E. B. Feldman·M. A. Yurishchev
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Abstract

Recent magnetic susceptibility measurements for polycrystalline samples of binuclear nitrosyl iron complexes [Fe_2(C_3H_3N_2S)_2(NO)_4] (I) and [Fe_2(SC_3H_5N_2)_2(NO)_4] (II), suggest that quantum-mechanical entanglement of the spin degrees of freedom exists in these compounds. Entanglement E exists below the temperature T_E that we have estimated for complexes I and II to be 80-90 and 110-120 K, respectively. Using an expression of entanglement in terms of magnetic susceptibility for a Heisenberg dimer, we find the temperature dependence of the entanglement for complex II. Having arisen at the temperature T_E, the entanglement increases monotonically with decreasing temperature and reaches 90-95% in this complex at T=25 K, when the subordinate effects are still small.

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S. M. Aldoshin, E. B. Feldman, M. A. Yurishchev. 2009-02-19. Quantum Entanglement in Nitrosyl Iron Complexes. https://doi.org/10.1134/s1063776108110101

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