TY - JOUR
T1 - An electron-counting rule to determine the interlayer magnetic coupling of the van der Waals materials
AU - Xiao, Jiewen
AU - Yan, Binghai
N1 - We thank helpful discussions with H X Fu and C X Liu. B Y acknowledges the financial support by the Willner Family Leadership Institute for the Weizmann Institute of Science, the Benoziyo Endowment Fund for the Advancement of Science, Ruth and Herman Albert Scholars Program for New Scientists.
PY - 2020/10
Y1 - 2020/10
N2 - In layered magnetic materials, the magnetic coupling between neighboring van der Waals layers is challenging to understand and anticipate, although the exchange interaction inside a layer can be well rationalized for example by the superexchange mechanism. In this work, we elucidate the interlayer exchange mechanism and propose an electron-counting rule to determine the interlayer magnetic order between van der Waals layers, based on counting the d-orbital occupation (dn, where n is the number of d-electrons at the magnetic cation). With this rule, we classify magnetic monolayers into two groups, type-I (n<5�<5) and type-II (n ≥ 5), and derive three types of interlayer magnetic coupling for both insulators and metals. The coupling between two type-II layers prefers the antiferromagnetic (AFM) order, while type-I and type-II interface favors the ferromagnetic (FM) way. However, for two type-I layers, they display a competition between FM and AFM orders and even lead to the stacking dependent magnetism. Additionally, metallic layers can also be incorporated into this rule with a minor correction from the free carrier hopping. Therefore, this rule provides a simple guidance to understand the interlayer exchange and further design van der Waals junctions with desired magnetic orders.
AB - In layered magnetic materials, the magnetic coupling between neighboring van der Waals layers is challenging to understand and anticipate, although the exchange interaction inside a layer can be well rationalized for example by the superexchange mechanism. In this work, we elucidate the interlayer exchange mechanism and propose an electron-counting rule to determine the interlayer magnetic order between van der Waals layers, based on counting the d-orbital occupation (dn, where n is the number of d-electrons at the magnetic cation). With this rule, we classify magnetic monolayers into two groups, type-I (n<5�<5) and type-II (n ≥ 5), and derive three types of interlayer magnetic coupling for both insulators and metals. The coupling between two type-II layers prefers the antiferromagnetic (AFM) order, while type-I and type-II interface favors the ferromagnetic (FM) way. However, for two type-I layers, they display a competition between FM and AFM orders and even lead to the stacking dependent magnetism. Additionally, metallic layers can also be incorporated into this rule with a minor correction from the free carrier hopping. Therefore, this rule provides a simple guidance to understand the interlayer exchange and further design van der Waals junctions with desired magnetic orders.
UR - http://www.scopus.com/inward/record.url?scp=85089030608&partnerID=8YFLogxK
U2 - https://doi.org/10.1088/2053-1583/ab9ea4
DO - https://doi.org/10.1088/2053-1583/ab9ea4
M3 - مقالة
SN - 2053-1583
VL - 7
JO - 2D Materials
JF - 2D Materials
IS - 4
M1 - 045010
ER -