Emergence of Multispinterface and Antiferromagnetic Molecular Exchange Bias via Molecular Stacking on a Ferromagnetic Film. (22nd January 2020)

• Record Type: Journal Article
• Authors: Jo, Junhyeon; Byun, Jinho; Lee, Jaebyeong; Choe, Daeseong; Oh, Inseon; Park, Jungmin; Jin, Mi‐Jin; Lee, Jaekwang; Yoo, Jung‐Woo
• Is Part Of: Advanced functional materials. Volume 30:Number 11(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-01-22
• Subjects: density functional theory -- exchange bias -- molecular antiferromagnets -- molecular spinterface -- van der Waals interlayer coupling; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201908499
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Heterointerfaces may exhibit unexpected physical properties distinct from intrinsic properties of component materials. In particular, metal–organic interfaces can drive unique interfacial spin moments, which are often called molecular spinterface. Here, van der Waals stacking of molecular layers may lead to variations in the intra/interlayer exchange coupling resulting in multiple ground states, which is highly desired for multifunctional magnetic devices. In this report, the emergence of molecular multispinterface of paramagnetic cobalt‐octaethyl‐porphyrin (CoOEP) layers in a Fe/CoOEP heterostructure is demonstrated through the interfacial layer and a successive antiferromagnetic molecular spin chain. The disentangled interfacial ferromagnetic spins lead to multiple magnetic ground states and behave as additional spin‐dependent scattering centers, as evidenced through the magnetotransport study. In addition, the antiferromagnetic molecule spin chain derives tunable exchange bias, which signifies the dominance of the antiferromagnetic interfacial interaction. Theoretical calculations demonstrate spin configurations of the molecular chain and the antiferromagnetic interfacial coupling through oxygen intermediaries. The development of the molecular multispinterface and controllable exchange bias therein will provide a promising route for the active control of multivalued data processing at the nanoscale. Abstract : Heterointerfaces of paramagnetic planar CoOEP molecules on a ferromagnetic Fe film develop unique interfacial molecular magnetism, which also derives successive antiferromagnetic molecular spin chain. This multispinterface leads to tunable exchange bias and multiple magnetic ground states and behaves as additional spin‐dependent scattering centers, as evidenced through magnetometry and magnetotransport and their origin is unveiled by density functional theory calculations.