Minority Spin Channel Research Articles

D0 Half-Metallic Ferromagnetism in GeNaZ (Z = Ca, Sr, and Ba) Ternary Half-Heusler Alloys: an Ab initio Investigation

First-principles approach based on density functional theory was applied to investigate the structural, elastic, phonon dynamics, thermodynamics, electronic, and magnetic properties of GeNaZ (where Z = Ca, Sr and Ba) ternary Heusler alloys. The Perdew-Burke-Ernzerhof generalized gradient approximation (GGA) and the modified Becke-Johnson (mBJ-GGA) were used for the exchange-correlation energy and potential. The GeNaZ ternary Heusler alloys were found to be half-metallic and stable in the ferromagnetic α phase. The alloys were found to satisfy the criteria for dynamic and elastic stabilities. Thus, they are dynamically and elastically stable. The calculated spin-polarized electronic band structure and density of states using GGA (mBJ-GGA) reveal that the minority spin channel has metallic character and the majority spin channel having an electronic band gap of 0.26 (0.59), 0.39 (0.66), and 0.08 (0.33) eV for the GeNaCa, GeNaSr, and GeNaBa ternary Heusler alloys, respectively. The considered alloys all result in a stable ferromagnetic half-metallic ground state structure with a magnetic moment of 1 μB/cell. The density of states and the spin-charge density of these alloys show that the magnetization originates primarily from the 4p states of the Ge atoms. The GeNaZ ternary Heusler alloys do not have any magnetic elements, and their induced magnetism makes them very promising materials for spintronic devices.

Electronic structure calculations of some Cr based spintronic half Heusler alloys

Several XYZ materials with X and Y as 3d and 4d transition metal elements offer half-metallic magnetic properties. In such half-metallic materials there is a band gap at the Fermi energy for the minority spin channel, but not for the majority spin channel. In this work, we present the energy bands and density of states of half-Heusler alloys namely, KCrZ (where Z=S, Se and Te) using first principles full potential linearized augmented plane wave method by applying PBEsol approach of generalised gradient approximation. It is seen that these compounds show half-metallic character with large magnetic moment of about 5.0 μB Density of states and energy bands are analysed to discuss about the origin of large values of spin moment in such compounds.

Half-metallic stability of the Heusler alloys TiZrIrZ (Z = Al, Ga, and In) under volumetric strain and tetragonal deformation

The study of the structural, mechanical, and magneto-elctronic properties of TiZrIrZ (Z = Al, Ga, In) quaternary Heusler alloys was performed using full-potential linearized augmented plane-wave (FP-LAPW) method, based on the density functional theory (DFT) with generalized gradient approximation (GGA). The findings show that the ferromagnetic phase of Type I atomic arrangement is energetically favorable. The calculated spin-polarized band structures of TiZrIrZ (Z = Al, Ga, and In) reveal that they are half-metallic materials, with indirect band gaps (half-metallic gaps) of 1.01(0.41 eV), 0.96(0.37 eV), and 0.91 (0.43 eV) in the minority spin channel, respectively. The ferromagnetism of TiZrIrZ alloys is caused by the d-orbitals of Ti and Zr atoms and the total magnetic moments verify the Slater–Pauling rule: $$M_{t} = Z_{t} - 18$$. The calculated Curie temperatures of TiZrIrZ (Z = Al, Ga, and In) are 545 K, 566 K, and 574 K, respectively. Moreover, the half-metallicity of all these alloys is kept by the volumetric strain and tetragonal deformation in the relatively large ranges, for the lattice parameter and c/a ratio, respectively.

Anisotropy of resistivity in hexagonal late transition metals and their alloys

Transport properties of hexagonal transition metals Co, Ru, and Os at finite temperatures are studied by means of ab initio electronic structure techniques and the Kubo linear response theory. An alloy analogy model for a quantitative treatment of the electrical conductivities due to temperature-induced lattice vibrations (phonons) and spin fluctuations is applied with focus on anisotropy induced by the hexagonal structure. The resistivity anisotropy in Co is found opposite to that in Ru and Os, in agreement with existing experimental data. This result is ascribed to the strong itinerant ferromagnetism of Co which leads to profound differences in the electronic structure and conductivities in the majority and minority spin channels. A similar sensitivity to spin polarization is predicted for the anisotropy of residual resistivity in random hexagonal Co-rich Co–Ni and Co–Ni–Fe alloys.

Ductile and metallic nature of Co2VZ (Z= Pb, Si, Sn) Heusler compounds: A First Principles Study

Herein, optoelectronic, elastic and magnetic properties of L21 structured Co2VZ (Z= Pb, Si, Sn) full Heusler compounds have been investigated by two methods. One is full potential linearized augmented plane wave (FP-LAPW) method as implemented in WIEN2k and second is pseudo potential method as implemented in Atomistic Tool Kit-Virtual NanoLab (ATK-VNL). All these compounds shows zero band gap in majority spin channel in the both simulation codes and a finite band gap are 0.33 and 0.54 eV in Co2VZ (Z= Pb, Sn) alloys (semiconducting) respectively. Due to minority-spin channel near the Fermi level as implemented in WIEN2k code and showing 100% spin polarization except Co2VSi (metallic) with zero band gap. These compounds found to be perfectly half-metallic ferromagnetic (HMF). However, above mentioned compounds shows finite band gaps in ATK-VNL code. The calculated magnetic moment of these compounds Co2VZ (Z= Pb, Si, Sn) are 3.00 and 3.00, 3.02 and 2.96, 3.00 and 3.00µB in WIEN2k and ATK-VNL codes respectively. Thus we have observed that the calculated vales by these simulation codes and Slater-Pauling rule have nice tuning. Optical properties of these compounds like as reflectivity, refractive index, excitation coefficient, absorption coefficient, optical conductivity and electron energy loss have been analyzed. Absorption coefficient and electron energy - loss function values are increases as we increase the value of energy. The vales of Pugh’s ratio B/G is greater than 1.75 for all compounds and showing ductile nature with positive value of Cauchy pressure (CP = C12 – C44) and shows metallic behavior of Co2VZ (Z= Pb, Si, Sn) compounds.

Investigation of structural, electronic, magnetic and mechanical properties of a new series of equiatomic quaternary Heusler alloys CoYCrZ (Z = Si, Ge, Ga, Al): A DFT study

The structural stability, band structure, density of states (DOS), magnetic and mechanical properties of Co-based equiatomic quaternary Heusler alloys (EQHAs) CoYCrZ (Z = Si, Ge, Ga, Al) are examined by employing 1st principle calculations in the framework of density functional theory (DFT) as embedded in Wien2k code. The generalized gradient approximation (GGA) of Perdew-Burke Ernzehrof (PBE) is used for all these calculations. The lattice constants obtained by the optimization of structures and Type-II is found the most stable configuration for all alloys. The band diagrams and DOS calculations show that all these materials possess half metallic (HM) character because they have band gap in minority spin channel. The origin of band gap has been explained which is due to the robust d-d hybridization among transition metals (TMs). The obtained magnetic moments (MMs) are in accordance to the Slater-Pauling rule. The considered materials have high MMs and all alloys showed 100% spin polarization (SP). Curie temperature has also been calculated and reported for all these alloys. In order to check the mechanical stability, the calculations for elastic constants and other mechanical parameters are carried out which have revealed that all alloys are stable and have ductile nature. All the considered alloys in this study are reported for the first time and no data is available for comparison. It is envisaged these alloys are suitable for spintronic applications as in magnetic tunnel junctions (MTJs), spin valves, and spin injectors etc.

Investigation of structural, electronic, magnetic and half-metallic properties in ternary zinc blende CrMoO and ScMoO by GGA and GGA+U method: First principles study

First principles calculations of zinc blende CrMoO and ScMoO in GGA and GGA + U methods are presented. Ferromagnetic states are predicted to be more stable than that of nonmagnetic and antiferromagnetic phases. CrMoO exhibits metallic properties in GGA method, whereas in GGA + U, it exhibits half-metallic ferromagnetism (HMF). ScMoO exhibits HMF in both approaches. In GGA + U, Mo deg orbitals in CrMoO are pushed below the EF in the valence band whereas Mo dt2g orbitals are raised above the EF in the conduction band forming a band gap of about 0.88 eV in the minority spin channel. In ScMoO, Mo-d orbitals split up at the EF creating a band gap of about 0.63 eV in the minority spin channel. Half-metallic CrMoO and ScMoO have the integer valued magnetic moments of 4.00 μB and 1.00 μB respectively, The compounds ScMoO and CrMoO exhibit 100% spin polarization having applications in the field of spintronics.

First principles study on the structural, electronic, mechanical and lattice dynamical properties of XRhSb (X = Ti and Zr) paramagnet half-Heusler antimonides

The half-Heusler TiRhSb and ZrRhSb alloys in the formation of face-centered cubic MgAgAs-type structure, which conforms to the space group with 216 as the space number, have been investigated using Generalized Gradient Approximation (GGA) implemented in Density Functional Theory (DFT). The calculated formation enthalpies and the plotted energy-volume curves of different types of structural phases (α, β, and γ) in these alloys indicate that the γ-phase structure is the best energetically suitable structure. In addition, TiRhSb and ZrRhSb alloys have been found as paramagnetic (PM) with the investigation of antiferromagnetic (AFM), ferromagnetic (FM), and paramagnetic (PM) orders in the most stable γ-phase structure. Therefore, their electronic, mechanical, and dynamical properties have been examined in the γ structural phase and paramagnetic order. These alloys have semiconducting nature due to the observed same band gaps in both the majority and minority spin channels of the calculated spin-polarised electronic band structure. These calculated band gaps are 0.75 eV for γ-TiRhSb and 1.18 eV for γ-ZrRhSb. The predicted elastic constants indicate that the alloys in this study are mechanically stable and show nearly isotropic behavior in the γ structural phase. Also, the minimum and the diffuson thermal conductivites have been determined for these alloys. Finally, the calculated phonon dispersion spectras for the γ-TiRhSb and γ-ZrRhSb half-Heusler antimonide alloys show the dynamic stability of these systems.

First-Principles Study of Ferromagnetism in Iron Chromite Spinels: FeCr2O4 and CrFe2O4

The structural, electronic and magnetic properties of FeCr2O4 and CrFe2O4 spinels have been investigated by the first-principles approach based on density functional theory (DFT) and the full-potential linearized augmented plane-wave method, within the generalized gradient approximation (GGA-PBE) and GGA-[Formula: see text] scheme. The stability of these spinels in the normal and inverse phases is evaluated. The spin-polarized electronic band structures and density of states of FeCr2O4 calculated by GGA-PBE and GGA-[Formula: see text] show that the minority spin channel has metallic nature and the majority spin channel has a half-metallic (HM) gap of 0.25[Formula: see text]eV and 1.30 eV, respectively. CrFe2O4 shows that both minority and majority spin channels have metallic nature when using GGA-PBE and half-semiconducting behavior with half-semiconductor gap of 0.71[Formula: see text]eV when using GGA-[Formula: see text], with magnetic moment of 2[Formula: see text][Formula: see text] per formula unit. Analysis of density of states of these compounds indicates that the magnetic moment mainly originates from the strong spin-polarization of 3[Formula: see text] states of Fe and Cr atoms. Presence of HMF in FeCr2O4 and CrFe2O4 spinels makes these compounds promising compounds for spintronic applications.

Investigation of Electronic Structure, Mechanical, Magnetic Properties and Thermal Properties of Co<sub>2</sub>CrSi<sub>1-x</sub>Al<sub>x</sub> Quaternary Heusler Alloys: An Ab-initio Study

The structural, electronic and elastic properties of full- Heusler alloys Co2CrZ (Z=Si,Al) and their quaternary compound Co2CrSi1-xAlx, are determined using the full potential linearized augmented plane waves (FP- LAPW) method based on (GGA) the Generalized Gradient Approximation and density functional theory (DFT) implemented in the WIEN2k package. As results, quaternary compound in CuHg2Ti-type crystal structure are stable. Density of states (DOS) and bands structure show the existence of energies band gaps in their minority-spin channels with half-metallic behavior. The lattice constant of new quaternary alloys Co2CrSi1-xAlx exhibits a small deviation from Vegard's law and a marginal deviation of the bulk modulus from linear concentration. The three independent elastic constants (C11, C12, and C44) are calculated from the direct computation of the stresses generated by small strains. Besides, we report the variation of the elastic constants as a function of pressure as well. From the calculated elastic constants, the mechanical character of Co2CrSi1-xAlx is predicted; elastic constants are calculated to investigate stability criteria and the mechanical nature of the studied materials. The quaternary compound is found to be mechanically anisotropic, ductile and meet the elastic stability criteria. A regular solution model is used to investigate the thermodynamic stability of the alloy which essentially shows a miscibility gap phase by calculating the critical temperatures of the alloys.

Studi Teoritis Pembentukan Momen Magnetik pada Alloy half-Heusler Mn2Ge

Heusler alloyalloy is a subclass material that consists of transition metal compounds with fascinating magnetic properties due to their magnetic moment value that is still studied by many researchers due to their magnetic moment value that can be predicted using a simple calculation called Slater-Pauling rule (SP rule)s. According to the SP rule, when the total number of the valance electron gives a value of 18 (for half-Heusler alloy), the magnetic momen of this material is predicted by the value of 0 μB. By using this simple calculation, one can make material that have zero magnetic moment value. On the other hand, those this materials generally hasve halfhalf-metallic behavior in which the spin orientation only occurs on the one direction of either in the majority or minority spin channel. Starting from those issues, we propose a theoretical study to investigate the magnetic moment formation of halfhalf-Heusler alloyalloy Mn2Ge. Our results show that Mn2Ge have magnetic moment of 0.03 μB and show the halfhalf-metallic feature of Mn2Ge.

Spin polarization effect on the ground state and electronic properties of ErCu using DFT and DFT+U approaches

Using first principles total energy calculation with the approach of density functional theory (DFT) and DFT + U calculations, the structural and electronic properties of erbium copper (ErCu) intermetallic compound were studied. In the present work, we used the local density approximation for the exchange and correlation potential for the spin polarized case. The structural optimization shows that ErCu is stable in the cubic structure. The obtained ground state properties viz; lattice constant ao (a.u), bulk modulus B (GPa) and magnetic moment (μB), which show good comparison with the available experimental data. We have also investigated the electronic properties such as electronic band structure, density of states, Fermi surfaces and charge density of states for spin-polarized case. In the band structure, majority spins energies contributions are higher than the minority spins energies contribution. The total density of states (TDOS) show that near the Fermi level, is mostly dominated by Er ‘f’ orbital electrons and below the Fermi level, are due to Cu ‘3d’ orbital electrons. The charge distributions of ErCu are ranging between +0.0003 e/Å3 to +0.0693 e/Å3 for majority channels and +0.0003 e/Å3 to +0.0715 e/Å3 for the minority spin channels.

Inducing half metallicity with alloying in Heusler Compound CoFeMnSb

First principles studies were performed in order to find out the possibility of inducing half-metallicity in Heusler Compound CoFeMnSb, by means of alloying it with 3d-transition metal elements. Proper alloying element is selected through the calculations of formation energies. These calculations were tested with different concentrations of alloying elements at different atomic sites. Among the selected transition metal elements Sc and Ti are proposed to be excellent alloying elements, particularly at Mn site. By using these alloying elements complete half metallic behaviour is obtained in , , , , and CoFeTiSb alloys. Shifting of Co–Fe d-states towards lower energy region leads to zero density of states at Fermi level for the spin minority channel. Alloying effects on the electronic structure and magnetization are discussed in details. Thermodynamical stability of these new alloys is a major part of this study. The Curie temperatures of and were found to be 324.5 K and 682 K; respectively, showing good candidature for spintronics applications. For understanding the bonding nature of the constituent atom of CoFeMnSb, crystal orbital Hamiltonian populations have been analysed.

Magnetic orders and electronic behaviours of new chalcogenides Cu3MnCh4 (Ch = S, Se and Te): An ab initio study

ABSTRACTThe ternary copper-based chalcogenides Cu3MnCh4 (Ch = S, Se and Te), which have simple cubic (SC) crystal structure and conform to space group with 215 space number, have been investigated by spin-polarised Generalised Gradient Approximation (GGA) in the framework of Density Functional Theory (DFT). First, all systems have been considered in ferromagnetic (FM) and three different type antiferromagnetic (AFM) orders which are A-type (A-AFM), G-type (G-AFM) and C-type (C-AFM) to investigate most stable magnetic phase for each system. The energetically favoured magnetic phase is A-type AFM for Cu3MnS4 and Cu3MnSe4 compounds, while Cu3MnTe4 compound has FM ground state. The electronic band structures of these systems have been investigated, after the well-optimised structural parameters in their stable magnetic phase have been obtained. The calculated spin-polarised electronic band structure of FM Cu3MnTe4 compound exhibits half-metallic behaviour with a band gap in minority spin channel (Eg = 0.99 eV) while metallic band structure is observed for majority spin. The calculated electronic band structures in A-type AFM phase for Cu3MnS4 and Cu3MnSe4 systems show that Cu3MnS4 compound has semiconducting behaviour with a small band gap (Eg = 0.21 eV) whereas Cu3MnSe4 compound has metallic character. The calculated negative formation enthalpies indicate the thermodynamic stability and structural synthesisability of these compounds.

Structural, elastic, mechanical, electronic, magnetic, thermoelectric and thermodynamic investigation of half metallic double perovskite oxide Sr2MnTaO6

Abstract Experimental lattice constant has been used for theoretical predictions on structural, elastic, mechanical, electronic magnetic thermoelectric and thermodynamic properties of Sr2MnTaO6 double perovskite oxide within well-known ab-initio density functional theory. Optimized lattice constant has been employed for obtaining spin involved electronic structure results within generalized gradient approximation (GGA), Hubbard approximation (GGA + U) and modified Becke Johnson approximation (mBJ). Electronic results show half-metallic nature with majority spin channels as metallic and minority spin channels as semi-conducting. Magnetic moment calculated within GGA + U was found equal to 4 µb. Calculated large value of Bulks modulus (B) and Young modulus (Y) characterize it as hard and stiffer material. Pugh ratio (B/G) and Cauchy pressure (C12–C44) portray its brittle nature. Using Boltztrap code we have calculated the variation of electrical conductivity (σ/τ), Seebeck coefficient (S), electronic thermal conductivity (k/τ) and Power factor (PF) in both spin channels. (σ/τ) is found to have decreasing nature in spin up states and increasing nature in spin down states, hence confirms the metallic nature in spin up states and semi-conducting in spin down states. Seebeck coefficients (S) reveal the presence of positive charge carriers in spin up states and negative in spin down states. The computed value of total power factor was found to be 1.99 × 1012 WK−2 m−1 s−1 at 1000 K. Furthermore, we have computed pressure and temperature dependent thermodynamic parameters for this compound in the temperature range of 0 K to 1000 K and pressure range of 0 GPa to 18 GPa with a step size of 3 GPa.

Symmetry aspects of spin filtering in molecular junctions: Hybridization and quantum interference effects

Control and manipulation of electric current and, especially, its degree of spin polarization (spin filtering) across single molecules are currently of great interest in the field of molecular spintronics. We explore one possible strategy based on the modification of nanojunction symmetry which can be realized, for example, by a mechanical strain. Such modification can activate new molecular orbitals which were inactive before due to their orbital mismatch with the electrode's conduction states. This can result in several important consequences such as (i) quantum interference effects appearing as Fano-like features in electron transmission and (ii) the change in molecular level hybridization with the electrode's states. We argue that the symmetry change can affect very differently two majority- and minority-spin conductances and thus alter significantly the resulting spin-filtering ratio as the junction symmetry is modified. We illustrate the idea for two basic molecular junctions: Ni/benzene/Ni (perpendicular vs tilted orientations) and Ni/Si chain/Ni (zigzag vs linear chains). In both cases, one highest occupied molecular orbital (HOMO) and one lowest unoccupied molecular orbital (LUMO) (out of HOMO and LUMO doublets) are important. In particular, their destructive interference with other orbitals leads to dramatic suppression of majority-spin conductance in low-symmetry configurations. For a minority-spin channel, on the contrary, the conductance is strongly enhanced when the symmetry is lowered due to an increase in hybridization strength. We believe that our results may offer a potential route for creating molecular devices with a large on-off ratio of spin polarization via quantum interference effects.

Surface Recombination in Ultra-Fast Carrier Dynamics of Perovskite Oxide La0.7Sr0.3MnO3 Thin Films

Aspects of the optoelectronic performance of thin-film ferromagnetic materials are evaluated for application in ultrafast devices. Dynamics of photocarriers and their associated spin polarization are measured using transient reflectivity (TR) measurements in cross linear and circular polarization configurations for La0.7Sr0.3MnO3 films with a range of thicknesses. Three spin-related recombination mechanisms have been observed for thicker films (thickness of d ≥ 20 nm) at different time regimes (τ), which are attributed to the electron-phonon recombination (τ < 1 ps), phonon-assisted spin-lattice recombination (τ ∼ 100 ps), and thermal diffusion and radiative recombination (τ > 1 ns). Density functional theory (DFT+U) based first-principles calculations provide information about the nature of the optical transitions and their probabilities for the majority and the minority spin channels. These transitions are partly responsible for the aforementioned recombination mechanisms, identified through the comparison of linear and circular TR measurements. The same sets of measurements for thinner films (4.4 nm ≤ d < 20 nm) revealed an additional relaxation dynamic (τ ∼ 10 ps), which is attributed to the enhanced surface recombination of charge carriers. Our DFT+U calculations further corroborate this observation, indicating an increase in the surface density of states with decreasing film thickness which results in higher amplitude and smaller time constant for surface recombination as the film thickness decreases.

Effect of atomic ordering on structural, electronic and magnetic properties of Co2Cr0.5Fe0.5Al Heusler alloy

Abstract The effect of substitution of Fe in place of Cr on structural, electronic and magnetic properties of quaternary Co2Cr0.5Fe0.5Al Heusler alloy has been investigated. The study of X-ray diffraction (XRD) and Mossbauer spectroscopy of annealed sample have a highly ordered B2-type phase. The parameters extracted from the XRD have been used to analyze half metallicity of B2-phase theoretically. The first principal calculations based on generalized gradient approximation predict half metallic ferromagnetic with an energy gap of 0.319 eV in the minority spin channel around the Fermi level. On substitution of Fe in Co2CrAl, DC magnetization studies show an increase in saturation magnetization (3.02 µB/f.u.) and Curie temperature (910 K) compared to its parent alloy Co2CrAl at room temperature. Structural, electronic and magnetic properties of quaternary Co2Cr0.5Fe0.5Al Heusler alloy show that the half metallicity is retained even on partial substitution of Cr by Fe with predominant B2 ordered structure. Thus Co2Cr0.5Fe0.5Al in B2-phase brings excellent structural ordering, high magnetic moment and Curie temperature while retaining the half-metallicity that is useful for spintronics applications.

Investigation of new d0 half-metallic full-heusler alloys N2BaX (X=Rb, Cs, Ca and Sr) using first-principle calculations

The first-principle density functional theory (DFT) calculations were employed to investigate the structural, elastic, electronic, magnetic properties and half-metallicity of N2BaX (X = Rb, Cs, Ca and Sr) new d0 half-metallic full-Heusler compounds with Hg2CuTi-type and Cu2MnAl-type structures within generalized gradient approximation Perdew, Burke, and Ernzerhof GGA-PBE and the modified Becke-Johnson potential mBJ-GGA-PBE for the exchange correlation potential. Total energy calculations show that formation of these alloys in Cu2MnAl-type structure are energetically favorable and are more stable in the ferromagnetic phase than Hg2CuTi-type structure. We have found that N2BaX (X = Rb, Cs, Ca and Sr) alloys in Cu2MnAl-type structure are half-metallic ferromagnets with an integer total magnetic moment at the equilibrium lattice constant, which were in agreement with Slater–Pauling rule (Mtot = 16-Ztot). The half-metallicity was discussed for N2BaX using the energy band structure, our calculations show that the minority spin channel has metallic nature and the majority spin channel has a wide semiconducting gap of 3.78, 4.60, 5.44 and 3.74eV and they has a huge half-metallic gap of 1.56, 2.33, 2.39 and 1.59 eV for N2BaCa, N2BaCs, N2BaRb and N2BaSr respectively with the mBJ-GGA-PBE.

Electronic structure, magnetism properties and optical absorption of organometal halide perovskite CH3NH3XI3 (X = Fe, Mn)

The electronic structure, magnetism properties and optical absorption of organometal halide perovskite CH3NH3XI3 (X = Fe, Mn) are studied using the first principles calculations by the generalized gradient approximation (GGA) and the GGA + U method, respectively. The magnetic ground states of CH3NH3MnI3 and CH3NH3FeI3 are both the G-type antiferromagnetic (AFM) order. With the introduction of on-site Coulomb interactions U, CH3NH3FeI3 shows the semiconducting phase from original metallic state predicted by the GGA method. The band gap value of CH3NH3MnI3 with the G-AFM state is 1.68 eV, while the band gap in the spin majority channel is 0.694 eV and the band gap in the spin minority channel is 2.147 eV when system is in FM state. For CH3NH3FeI3 system, the band gap is 0.957 eV when system is in G-AFM state, while the band gap in the spin majority channel is 0.602 eV and the band gap in the spin minority channel is 1.215 eV when system is in FM state, which shows that photo-excited electrons of CH3NH3MnI3 and CH3NH3FeI3 with FM state will rapidly melt the local magnetic order. Furthermore, the optical properties of CH3NH3MnI3 and CH3NH3FeI3 are calculated. CH3NH3MnI3 with the FM state shows strong infrared light absorption. CH3NH3FeI3 with FM state have stronger infrared absorption than that in G-AFM state.