First-principles investigations on the Berry phase effect in spin–orbit coupling materials

AbstractWe have derived an expression of the Dzyaloshinskii–Moriya interaction (DMI), where all the three components of the DMI vector can be calculated independently, for a general, non-collinear magnetic configuration. The formalism is implemented in a real space—linear muffin-tin orbital—atomic sphere approximation (RS-LMTO-ASA) method. We have chosen the Cr triangular trimer on Au(111) and Mn triangular trimers on Ag(111) and Au(111) surfaces as numerical examples. The results show that the DMI (module and direction) is drastically different between collinear and non-collinear states. Based on the relation between the spin and charge currents flowing in the system and their coupling to the non-collinear magnetic configuration of the triangular trimer, we demonstrate that the DMI interaction can be significant, even in the absence of spin-orbit coupling. This is shown to emanate from the non-collinear magnetic structure, that can induce significant spin and charge currents even with spin-orbit coupling is ignored.

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Systematic first-principles study of the on-site spin-orbit coupling in crystals

Physical Review B ◽

10.1103/physrevb.102.045109 ◽

2020 ◽

Vol 102 (4) ◽

Author(s):

Kensuke Kurita ◽

Takashi Koretsune

Keyword(s):

First Principles ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

First Principles Study

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Giant Magnetoresistance Calculated from First Principles

MRS Proceedings ◽

10.1557/proc-313-59 ◽

1993 ◽

Vol 313 ◽

Cited By ~ 28

Author(s):

W. H. Butler ◽

James M. MacLaren ◽

X.-G. Zhang

Keyword(s):

Low Temperature ◽

First Principles ◽

Giant Magnetoresistance ◽

Coherent Potential Approximation ◽

Orbit Coupling ◽

Approximation Technique ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Potential Approximation ◽

Magnetoresis Tance

ABSTRACTThe Layer Korringa Kohn Rostoker-Coherent Potential Approximation technique was used to calculate the low temperature Giant Magnetoresistance from first principles for Co|Cu and permalloy|Cu superlattices. Our calculations predict large giant Magnetoresis-tance ratios for Co|Cu and extremely large ratios for permalloy|Cu for current perpendicular to the layers. Mechanisms such as spin-orbit coupling which mix spin channels are expected to greatly reduce the GMR effect for permalloy|Cu.

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The Influence of Electronic Structure Modelling and Junction Structure on First-Principles Chiral Induced Spin Selectivity

10.26434/chemrxiv.12497690 ◽

2020 ◽

Author(s):

Martin Sebastian Zöllner ◽

Vladimiro Mujica ◽

Carmen Herrmann

Keyword(s):

Electronic Structure ◽

First Principles ◽

Density Functional ◽

Orbit Coupling ◽

First Principles Calculation ◽

Physical Parameters ◽

Theory Approach ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Junction Structure

<br>We have carried out a comprehensive study of the influence of electronic structure modeling and junction structure description on the first-principles calculation of the spin polarization in molecular junctions caused by the chiral induced spin selectivity (CISS) effect. We explore the limits and the sensitivity to modelling decisions of a Landauer / Green’s function / density functional theory approach to CISS. We find that although the CISS effect is entirely attributed in the literature to molecular spin filtering, spin-orbit coupling being partially inherited from the metal electrodes plays an important role in our calculations, even though this effect cannot explain the experi- mental conductance results. Also, an important dependence on the specific description of exchange interaction and spin–orbit coupling is manifest in our approach. This is important because the interplay between exchange effects and spin-orbit coupling may play an important role in the description of the junction magnetic response. Our calculations are relevant for the whole field of spin-polarized electron transport and electron transfer because there is still an open discussion in the literature about the detailed underlying mechanism and the magnitude of relevant physical parameters that need to be included to achieve a consistent description of the CISS effect<br>

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