Spin-Dependent Electronic Structure and Magnetic Anisotropy of Two

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C: Surfaces, Interfaces, Porous Materials, and Catalysis

Spin-Dependent Electronic Structure and Magnetic Anisotropy of Two-Dimensional SnO/FeN Heterostructures 4

Kai Nie, Xiaocha Wang, and Wenbo Mi J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.9b06896 • Publication Date (Web): 16 Aug 2019 Downloaded from pubs.acs.org on August 23, 2019

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The Journal of Physical Chemistry

Spin-Dependent Electronic Structure and Magnetic Anisotropy of Two-Dimensional SnO/Fe4N Heterostructures

Kai Nie1, Xiaocha Wang1,*, Wenbo Mi2

1Tianjin

Key Laboratory of Film Electronic & Communicate Devices, School of Electrical and

Electronic Engineering, Tianjin University of Technology, Tianjin 300384, China

2Tianjin

Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China

*Author

to whom all correspondence should be addressed.

E-mail: [email protected]

1 ACS Paragon Plus Environment

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ABSTRACT

Two-dimensional (2D) SnO monolayer has been attracted much attention owing to its unique electronic structure, which has the potential applications in high-performance electronic devices. However, it is necessary to induce the spin polarization in 2D SnO monolayer for its practical applications in spintronics. Here, the tunable spin-dependent electronic structure and magnetic anisotropy of SnO/Fe4N heterostructures are investigated systematically by first-principles calculations. The spin polarization and magnetism are induced in monolayer SnO by the interfacial proximity of Fe4N substrates. Except for model 1, the SnO monolayer shows the perpendicular magnetic anisotropy (PMA) in different stacking patterns. By comparing to other stacking patterns, Fe4N in model 2 shows a larger interfacial and inner PMA, where the maximum value reaches 2.34 mJ/m2. However, at a tensile strain of 2%, the layer V of Fe4N shows a transition from PMA to IMA. At a compressive strains of -4% and -6%, the layer IV, V and VII of Fe4N turn from PMA to IMA. Importantly, the monolayer SnO in model 2 shows PMA at a strain from -6% to 6%. These results suggest that the 2D SnO/Fe4N heterostructures have the potential applications in low-dimensional spintronic devices.


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 INTRODUCTION

Since the discovery of graphene,1 two dimensional (2D) materials have attracted much attention owing to its unique lattice structure, high-speed carrier mobility and mechanical properties, etc.2-5 However, some intrinsic deficiencies limit its practical applications in electronic devices, such as the zero band gap in the graphene and relatively low carrier mobility in transition metal dichalcogenides.6 Thus, it is necessary to find other 2D materials with desired physical properties. Recently, the 2D Tin monoxide (SnO) monolayer, a transparent semiconducting oxide, has always been paid much attention due to its good oxidation resistance and bipolar conductivity, etc.7-10 Till now, the electronic and magnetic properties of SnO monolayer have been studied for the practical applications in spintronics.11,12 Wang et al. illustrated that 3d transition metal atoms doping can induce the magnetism in SnO monolayer.13 Tao et al. reported that B-, C-, N-, O- and F-adsorption can tailor the magnetic and electronic properties of SnO monolayer.14 Generally, the spin polarization and magnetism can be induced in 2D semiconductors by different methods, such as surface defect,15 transition metal atom doping and adsorption.16,17 However, these methods are difficult to control precisely in experiments. Therefore, it necessary to deposit the SnO monolayer on the magnetic substrates, which is expected to introduce the spin polarization in SnO monolayer by magnetic proximity effect.18,19 The magnetic proximity effect can effectively induce the spin polarization in 2D monolayer semiconductors, such as WTe2/Fe3O4(111), graphene/Fe4N(111) and MoS2/Fe4N(111) heterostructures.20-22 Yang et al. illustrated the graphene can strongly enhance the perpendicular magnetic anisotropy (PMA) of Co films, which indicates the magnetic anisotropy energy (MAE) of 2D materials/ferromagnet interfaces can be modulated.23,24 In magnetic proximity effect, the ferromagnetic substrate with a large spin polarization and a high Curie temperature is 3 ACS Paragon Plus Environment


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important, where the cubic Fe4N has a large spin polarization and a high Curie temperature of 760 K.25,26 Moreover, a small lattice mismatch appears between SnO monolayer and Fe4N(001). In the 2D nonmagnetic SnO/ferromagnetic Fe4N heterostructures, the magnetic proximity effect can induce the spin polarization and magnetic moment in monolayer SnO. Meanwhile, the interfacial coupling can also influence the magnetism of Fe4N, especially the magnetic anisotropy. Moreover, PMA at ferromagnetic/oxide interfaces is very important in magnetic random access memories with low energy consumption and high thermal stability.27 Generally, the chemical vapor deposition (CVD) method can prepare the van der Waals heterostructures.28 Recently, CVD, direct growth, and van der Waals epitaxy methods have already been used to fabricated many vertical heterostructures, such as MoSe2/Bi2Se3 and WS2/MoS2.29,30 Therefore, the 2D SnO/Fe4N heterostructure may be fabricated by depositing the 2D SnO on Fe4N surface in experiments. In this work, the electronic structure and magnetic properties of 2D SnO/Fe4N heterostructures are investigated by first-principles calculations. It is demonstrated that the spin polarization and magnetic moment can be induced in SnO monolayer by the interfacial proximity of Fe4N substrates. By comparing to other stacking patterns, the Fe4N in model 2 shows a larger interfacial and inner PMA, where the maximum value reaches 2.34 mJ/m2. However, at a critical biaxial strain, the layer IV, V and VII of Fe4N shows a transition from PMA to IMA. Importantly, the monolayer SnO in model 2 shows PMA at a strain from -6% to 6%. The PMA in the highly spin-polarized SnO/Fe4N heterostructures can establish the foundations of low-dimensional spintronic devices.

 CALCULATION DETAILS AND MODELS

The first-principle calculations are performed by Vienna ab initio simulation package based on 4 ACS Paragon Plus Environment

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density functional theory (DFT) and the projector augmented wave method.31,32 The spin-polarized generalized gradient approximation with Perdew-Burke-Ernzerh functional is used.33 The energy cutoff for the plane-wave basis set is 500 eV. The Brillouin zone is sampled with 7×7×7 and 7×7×1 k meshes for bulk Fe4N and SnO/Fe4N heterostructures, respectively. The convergence criteria for the energy and atomic force are set to 1×10-5 eV and 0.01 eV/Å, respectively. In all the models, a 20-Å thick vacuum layer along z direction is employed to avoid the interaction between the top and bottom surfaces of the adjacent slabs. By comparing the electronic structure calculated with and without the spin-orbit coupling (SOC), it is found that SOC has little impact on the calculated results. Therefore, SOC is not considered in the calculations on the electronic structure. The lattice structures of monolayer SnO and bulk Fe4N are shown in Figures 1a and b. Fe4N has a cubic antiperovskite-type structure, where N atom locates at the body-centered site, and two types of Fe atoms occupy the corner (Fe1) and face-centered (Fe2) sites.22 Monolayer SnO has a tetragonal lattice structure, where each Sn atom locates at the apex of a square pyramid formed by four O atoms.34 The 2D SnO/Fe4N heterostructures are built by attaching the monolayer SnO (1×1) on top of one unit cell of Fe4N(001) (7 atomic layers). By the periodic boundary conditions, bulk Fe4N contains two interfaces, as shown in Figure 1b. We choose the Fe1/Fe2 and Fe2/N surfaces as the terminations. The monolayer SnO has three positions, where the Sn, O atom and hole occupies a central site, respectively. So, six different stacking patterns are considered including model 1 (Fe1/Fe2-O), model 2 (Fe2/N-O), model 3 (Fe1/Fe2-Sn), model 4 (Fe2/N-O), model 5 (Fe1/Fe2-hole) and model 6 (Fe2/N-hole) for SnO/Fe4N heterostructures, as shown in Figure 2. In order to confirm the stability of the heterostructures, the binding energy Ead = ET - ESnO - EFe4N is calculated, where ET, ESnO and EFe4N represent the total energy of the heterostructures, the



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Figure 1. Lattice structure of (a) monolayer SnO and (b) bulk Fe4N. Total and partial density of states (DOS) of (c) monolayer SnO and (d) bulk Fe4N.

isolated energy of monolayer SnO and Fe4N (7 atomic layers), respectively. For illustrating the charge transfer at SnO/Fe4N interface, the charge density difference ∆ρ = ρFe4N/SnO - ρFe4N - ρSnO, is calculated, where ρFe4N/SnO is the total charge density of the SnO/Fe4N heterostructures, ρFe4N and ρSnO are the charge density of isolated Fe4N(001) and monolayer SnO, respectively. The spatial spin polarization (SSP) is defined as P(r, z, ε) =

n↑s (r, z, ε) - n↓s (r, z, ε) n↑s (r, z, ε) + n↓s (r, z, ε)

, where n↑(↓) s (r, z, ε) is the spin-up

(down) charge density in real space with the energy interval of [𝜀, EF] at position r and distance z. Based on the second-order perturbation theory,35,36 MAE can be calculated by MAE ∝ ξ2 ∑o,u

|⟨ψo│Lz│ψu⟩|2

-

Eu -

|⟨ψo│Lx│ψu⟩|2 , where ψo and ψu are the occupied and unoccupied states, Eo and Eu are Eo

the eigen energies of the occupied and unoccupied states, ξ is the SOC constant. MAE depends on the couplings between the occupied and unoccupied states through the orbital angular momentum operators Lx and Lz. The small energy separation (Eu, Eo) between the occupied and unoccupied states is responsible for the variation of MAE. Finally, MAE can be obtained by MAE=E[100]-E[001], where E[100] and E[001] are the energies with the magnetization in the [100] and 6 ACS Paragon Plus Environment

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Figure 2.

Side and top views of 2D SnO/Fe4N heterostructures.

[001] directions.37,38 Positive and negative MAE indicate that the easy axis of the magnetization is perpendicular and parallel to the interface of the heterostructures, respectively.

 RESULTS AND DISCUSSION

The relaxed lattice constants of the individual Fe4N (7 atomic layers) and monolayer SnO are 3.795 and 3.830 Å, which are in well agreement with previous results.22,26 Therefore, a lattice mismatch of 0.918% appears between Fe4N (7 atomic layers) and monolayer SnO. Figure 1c shows the total density of states (TDOS) and partial density of states (PDOS) of monolayer SnO. The TDOS of monolayer SnO is symmetric distribution between spin-up and spin-down states. It is 7 ACS Paragon Plus Environment


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clear that the monolayer SnO is a semiconductor with an indirect band gap of 3.074 eV. Moreover, a strong hybridization appears between the Sn p state and O s state at valence band maximum (VBM), where the conduction band minimum (CBM) is governed by O p state as well as Sn s and p states hybridization. At Fermi level, TDOS of bulk Fe4N mainly comes from the spin-down channel, as shown in Figure 1d. In the energy range from -8.5 to -5 eV, a strong hybridization appears between N p and Fe2 d states, but in this energy range the N atom shows hardly any hybridization with Fe1 d state. The average magnetic moments of Fe1, Fe2, and N atoms are 2.940, 2.350, and 0.025 μB, which are in well agreement with previous results.22 Table 1 lists the binding energy (Ead) of six different stacking patterns, where the negative value suggests that the interfaces are stable. The structure parameters of six different stacking patterns are also listed in Table 1, such as the interlayer distance (D) and the distance (dFe-Sn)

Table 1 Binding energy (Ead), interlayer distance between monolayer SnO and Fe4N (D), the bond length between Fe and the nearest Sn atom (dFe-Sn), magnetic moment of Fe1 (µFe1), Fe2 (µFe2) and SnO layer (µSnO), and the band gap (Eg) at the most stable state of all the models.

model

Ead/eV

D/Å

dFe-Sn/Å

µFe1/µB

µFe2/µB

µSnO/µB

Eg/eV

1

-1.012

2.366

2.995

2.957

2.680

-0.033

3.165

2

-1.445

2.858

2.797

-

2.55

0.063

3.325

3

1.018

2.559

2.578

3.173

2.538

-0.033

-

4

-0.570

3.121

3.121

-

2.11

0.054

2.964

5

-2.641

2.426

2.435

3.096

2.214

-0.04

3.032

6

-1.903

2.008

2.684

-

1.485

-0.063

2.953


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between Sn and its nearest Fe atom. The most stable stacking pattern is model 5, where the binding energy is -2.641 eV with an equilibrium interlayer distance of 2.426 Å. The binding energy of model 1, 2, 4 and 6 is -1.012, -1.445, -0.570 and -1.903 eV with an interlayer distance of 2.366, 2.858, 3.121 and 2.008 Å. The binding energy of model 3 is 1.018 eV with an interlayer distance of 2.559 Å, which is not stable. Therefore, in the next sections, the calculations focus on model 1, 2, 4, 5 and 6. In order to demonstrate the change of the electronic states of monolayer SnO due to the magnetic proximity effect of Fe4N substrate, the band structure of monolayer SnO and SnO/Fe4N heterostructures has been calculated. In Figure 3, the band structure shows obvious changes due to the interaction between monolayer SnO and Fe4N substrate, where the red line represents the band of SnO. The asymmetric band structure suggests that the spin polarization can be induced in monolayer SnO, which originates from the interfacial magnetic proximity of Fe4N(001) substrate.

Figure 3. (a) Band structure of monolayer SnO. Band structure of SnO/Fe4N heterostructures (b) model 1, (c) model 2, (d) model 4, (e) model 5 and (f) model 6. The contribution of SnO and Fe4N is labeled with red and gray lines, respectively.



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In model 1, 2, 5 and 6, the SnO strongly hybridizes with Fe4N, inducing a half-semiconducting character of monolayer SnO, as shown in Figures 3b, c, e and f. In model 4, although SnO hybridizes with Fe4N, the characteristics of SnO-related bands are similar to the free-standing monolayer, indicating a weak interaction, as shown Figure 3d. In the SnO/Fe4N heterostructures, the band gap (Eg) of monolayer SnO is listed in Table 1. By comparing to pristine monolayer, the band gap of SnO increases by 0.152, 0.321 and 0.019 eV in model 1, 2 and 5. However, the band gap of SnO in model 4 and 6 decreases by 0.049 and 0.06 eV, respectively. Figures 4a-c show the spin-polarized TDOS and PDOS of 2D SnO/Fe4N heterostructures. For example, the label Fe4N-I refers to layer I, as defined in Figure 2. In model 2, a strong hybridization among Sn s, Fe1 d, and p states of O and N appears around -0.19 eV, as shown in Figure 4a. In model 5, a hybridization appears between Fe d, Sn s and O p states, whereas N atom in the layer II of Fe4N has hardly any hybridization with SnO due to the interlayer distance is so large, as shown in Figure 4c. The model 6 has the minimum D (see Table 1), where one of Sn atoms has the nearest distance to Fe1 atom. Owing to the stacking pattern, a strong hybridization among Sn 4s, O py, N pz and Fe1 d states occurs around 0.20 eV, as shown in Figure 4b. The spatial distribution of spin polarization (SSP) of model 2 in the energy intervals of [EF-0.4 eV, EF] and [EF, EF+0.4 eV] is further investigated. In Figure 4d, at the energy of EF-0.4 eV, the SSP of SnO layer is positive. However, at the energy of EF+0.4 eV, the SSP of SnO layer has a large negative value. The SSP results indicate that the high spin polarization is widely distributed in 2D SnO/Fe4N(001) heterostructures. The average magnetic moment of Fe1, Fe2, and N atoms in 2D SnO/Fe4N(001) heterostructures is shown in Table 1. In model 1 and 5, the magnetic moment of Fe1 is 2.957 and


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Figure 4. Total and partial DOS of (a) model 2, (b) model 5 and (c) model 6. (d) Spatial distribution of spin polarization of model 2.

3.096 µB. The Fe1 magnetic moment is slightly enhanced by comparing to bulk because of a stronger hybridization with N than Sn and O atoms. In model 1, 2, 4, 5 and 6, the Fe2 magnetic moment is 2.680, 2.550, 2.11, 2.214 and 1.485 µB, respectively. In model 4, 5 and 6, Fe2 atom strongly hybridizes with Sn and O atoms, where Fe2 magnetic moment is slightly smaller than bulk. However, since a stronger hybridization with N than Sn and O atoms appears in model 1 and 2, 11 ACS Paragon Plus Environment


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Figure 5. Layer resolved MAE, (a) model 1, (b) model 2, (c) model 4, (d) model 5 and (e) model 6. (f) Charge density of states in different stacking patterns.

the Fe2 magnetic moment is slightly enhanced by comparing to bulk. A strong interfacial hybridization between Fe and Sn atoms results in the magnetic moment of monolayer SnO. The total magnetic moment of SnO layer is listed in Table 1. The total magnetic moment of SnO layer is in the range from -0.064 to 0.033 μB. Clearly, the magnetic moment depends on the relative position, with the highest value of -0.064 μB in model 6, where Sn has the shortest distance from Fe1. In order to investigate the charge transfer mechanism between Fe4N and monolayer SnO, the charge density differences of 2D SnO/Fe4N heterostructures are calculated. In Figure 5f, yellow (blue) represents the charge accumulation (depletion). Obvious charge accumulation appears at the interface, which strengthens the adhesion of monolayer SnO. In model 1, 2 and 5, the charge distribution between Fe and Sn are almost identical, as shown in Figure 5f. The charge loses from Fe and Sn atoms, and accumulates in the Fe-Sn bond region, reflecting the covalent bond 12 ACS Paragon Plus Environment

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characteristic across the interface. It is worth noting that some extra charge accumulates around N atoms. However, in model 4, no obvious charge density accumulates in the Fe-Sn bond region, showing an ionic-like bond characteristic. Additionally, more charge accumulates in the covalent Fe-Sn bond in model 6 by comparing to other stacking patterns, which is consistent with the shortest interlayer distance (Table 1) and the smallest magnetic moment of Fe2. In order to investigate the magnetic anisotropy energy (MAE) of SnO/Fe4N heterostructures, Figures 5 show the layer-solved MAE of SnO/Fe4N heterostructures with different stacking patterns. In model 1, Fe4N shows PMA in the layer II, III and VI, where the maximum PMA is 2.05 mJ/m2. Moreover, in model 2, Fe4N shows PMA, which the maximum value is 2.34 mJ/m2. By comparing with Co/graphene and Fe4N/MgO, Fe4N in model 2 shows a larger interfacial PMA.24,39 In model 4, Fe4N shows PMA except layer II and IV, where the maximum PMA is 2.231 mJ/m2. In model 5, Fe4N shows PMA except the layer III, where the maximum PMA is 0.874 mJ/m2. By comparing to model 4, the layer V of Fe4N in model 6 shows a transition from PMA to IMA, where the maximum PMA of 2.089 mJ/m2 appears at the layer VII. In Figure 6a, the monolayer SnO in different stacking patterns shows PMA except model 1. Additionally, PMA of monolayer SnO reaches the maximum in model 2, where PMA is 0.107 mJ/m2. Two kinds of Fe atoms locate at the interfaces of model 1 and 5. Owing to the different distances with N atom, Fe1 and Fe2 atoms have different magnetic properties, where the contribution to MAE is contrasting. In Figures 6b and c, the contributions from Fe1 and Fe2 in model 1 show a large positive value due to the matrix element differences between dyz and dx2-y2 orbitals. However, a negative contribution comes from Fe1 due to the matrix element differences between dxz and dxy orbitals, and a large negative contribution comes from Fe2 due to the matrix element differences between dxz and dyz orbitals as well as dz2 and dyz orbitals, which leads to a 13 ACS Paragon Plus Environment


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Figure 6. (a) Total MAE of monolayer SnO in heterostructures. The 3d orbital resolved MAE of Fe1 and Fe2 atoms in different stacking patterns, (b) model 1-Fe1, (c) model 1-Fe2, (d) model 2-Fe2, (e) model 4-Fe2, (f) model 5-Fe1, (g) model 5-Fe2 and (h) model 6-Fe2.

smaller negative contribution. This is the reason why the interfacial Fe4N layer shows IMA in model 1. Similarly, in model 5, the matrix element differences between dxy and dx2-y2 orbitals of Fe1 (Figure 6f) and Fe2 (Figure 6g) are opposite, but the positive contribution is larger than the negative contribution. Therefore, the interfacial Fe4N layer shows PMA in model 5. The interfacial Fe4N atomic layer has one kind of Fe atom (Fe2) in model 2, 4 and 6. In model 2 and 4, Fe2 atoms have similar contribution to MAE (see Figures 6d and e). In model 2 and 4, the MAE of Fe2 atom can be ascribed to the matrix element differences between dz2 and dyz orbitals as well as dxy and dx2-y2 orbitals, where all the contributions are positive. In model 2, Fe2 atom has a larger positive contribution due to the matrix element differences between dxy and dx2-y2 orbitals, which indicates that the interfacial Fe4N layer in model 2 has the maximum PMA. However, in model 6, Fe2 contribution shows small negative values due to the matrix element differences between dz2 and dyz orbitals, as shown in Figure 6h. The in-plane biaxial strain is an effective method to modulate the MAE of SnO/Fe4N 14 ACS Paragon Plus Environment

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heterostructures. By comparing to other stacking patterns, model 2 has a larger PMA in the spin-polarized Fe4N, which will expand the practical applications in spintronic devices. Therefore, model 2 is chosen to simulate the magnetic anisotropy under the in-plane biaxial strain. The magnitude of strain is defined as ε = (a - a0)/a0, where a and a0 are the lattice constants of the strained and unstrained systems, respectively. Figure 7 shows the layer resolved MAE of model 2 at a strain from -6% to 6%. At a biaxial strain of 4%, 6% and -2%, Fe4N shows PMA except the layer II, where the maximum value is 2.142 mJ/m2. However, the layer V of Fe4N shows a transition from PMA to IMA at a tensile strain of 2%. The layer IV, V and VII of Fe4N turn from PMA to IMA at a compressive strain of -4% and -6%. Importantly, in model 2, the monolayer SnO shows PMA at a strain from -6% to 6%. It is clear that the PMA of monolayer SnO can be modulated by

Figure 7. Layer resolved MAE of model 2 at a strain from -6% to 6%.



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Figure 8. 3d orbital resolved MAE of Fe2 atom in model 2 at a strain of (a) 2%, (b) 4%, (c) 6%, (d) -2%, (e) -4% and (f) -6%.

biaxial strain, where the value changes from 0.025 to 0.59 mJ/m2. In order to further clarify the bonding mechanism, the insets of Figure 7 shows the charge density difference. As the in-plane biaxial strain changes from -6% to 6%, more charge accumulates in the Fe-Sn bond region, which leads to a stronger interfacial interaction. Figures 8a-f show the d-orbital resolved MAE of Fe2 atom in model 2 at different in-plane biaxial strains. At a strain from -6% to 6%, the Fe2 contributions from the matrix element differences between dxy and dx2-y2 orbital as well as dyz and dz2 orbital are positive. It is clear that the contribution slightly decreases as a tensile strain increases from 0% (Figure 6c) to 6% (Figures 8a-c). However, the contributions increases initially, then decreases by increasing the compressive strain form 0% (Figure 6c) to -6% (Figures 8d-f). It is worth noting that the Fe2 contribution shows the maximum value at a compressive strain of -2%. Furthermore, the biaxial strain have already been reported in many ultrathin 2D systems, such as graphene and MoS2 by using either the three-point bending configuration or piezoelectric substrates.40,41 Therefore, the biaxial strain can be realized in experiments. 16 ACS Paragon Plus Environment

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 CONCLUSION The tunable spin-dependent electronic structure and magnetic anisotropy of monolayer SnO/Fe4N heterostructures are investigated systematically by first-principles calculations. The spin polarization and magnetism are induced in monolayer SnO by the interfacial proximity of Fe4N substrates. By comparing to other stacking patterns, Fe4N in model 2 shows a larger interfacial and inner PMA, where the maximum value reaches 2.34 mJ/m2. In addition, at an in-plane biaxial strain of 4%, 6% and -2%, Fe4N shows PMA except for the layer II, where the maximum value of PMA is 2.142 mJ/m2. However, at a tensile strain of 2%, the layer V of Fe4N shows a transition from PMA to IMA. At a compressive strain of -4% and -6%, the layer IV, V and VII of Fe4N turn from PMA to IMA. Importantly, the monolayer SnO in model 2 maintains PMA at a strain from -6% to 6%. The above results lay the foundations for developing the low-dimensional spintronic devices.

■ AUTHOR INFORMATION Corresponding Authors *E-mail: [email protected] (X.W.).

Notes The authors declare no competing financial interest.

 ACKNOWLEDGMENTS

This work is supported by National Natural Science Foundation of China (51871161), the Key Project of the Natural Science Foundation of Tianjin City (18JCZDJC99400). 17 ACS Paragon Plus Environment


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 REFERENCES

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 TOC Graphic


Spin-Dependent Electronic Structure and Magnetic Anisotropy of Two

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