Low-Resistance Spin Filtering from Ferromagnet-Graphene-Ferromagnet Junctions

Nickel-graphene interfaces have been recently demonstrated to habor spin polarizations of up to 42{\%} with Ni/Graphene/MgO/Co heterostructures exhibiting negative out-of-plane magnetoresistances of 31{\%} [1]. These experiments agree qualitatively with theoretical predictions of spin filtering at planar Ni-Graphene and Co-Graphene interfaces [2]. We previously demonstrated room temperature magnetoresistance in vertical NiFe-Graphene-Co junctions [3]. Now we have fabricated high-quality NiFe(111)-Graphene-Co and NiFe(111)-Graphene-Fe junctions grown in-situ that exhibit high MR at room temperature while maintaining a very low interface resistance. Such junctions embody an excellent source of spin-polarized current for spintronics applications like fast and non-volatile magnetic random access memory. \\[4pt] [1] Martin et al., ACS Nano 8 (8), 7890, 2014.\\[0pt] [2] Karpan et al., Phys. Rev. Lett. 99, 176602, 2007\\[0pt [3] Cobas et al., Nano Letters 12, 3000, 2012.