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arXiv · 1403.5411

Quantum Monte Carlo study of one-dimensional transition metal organometallic cluster systems and their suitability as spin filters

L. Horváthová·R. Derian·L. Mitas·I. Štich
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Abstract

We present calculations of electronic and magnetic structures of vanadium-benzene multidecker clusters V$_{n}$Bz$_{n+1}$ ($n$ = 1 - 3) using advanced quantum Monte Carlo methods. These and related systems have been identified as prospective spin filters in spintronic applications, assuming that their ground states are half-metallic ferromagnets. Although we find that magnetic properties of these multideckers are consistent with ferromagnetic coupling, their electronic structures do not appear to be half-metallic as previously assumed. In fact, they are ferromagnetic insulators with large and broadly similar $\uparrow$-/$\downarrow$-spin gaps. This makes the potential of these and related materials as spin filtering devices very limited, unless they are further modified or functionalized.

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L. Horváthová, R. Derian, L. Mitas, I. Štich. 2014-03-21. Quantum Monte Carlo study of one-dimensional transition metal organometallic cluster systems and their suitability as spin filters. https://doi.org/10.1103/physrevb.90.115414

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