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The spintronic is an emerging technology which controls the properties of multifactional devices with spin of electrons. In present manuscript, Wien2k and Boltz Trap codes are used to explore electronic, magnetic, and thermoelectric characteristics of Sr 2 CrXO 6 (X = Nb, Mo) double perovskites (DPs). The evaluation of energies released in paramagnetic (PM), antiferromagnetic (AFM), and ferromagnetic (FM) states assure the stability of FM states. Both the negative formation energy and the tolerance factor confirm structural and thermodynamic stability in FM states. The 100 % spin polarization was confirmed by both integer values of magnetic moment (MM) and the spin polarization factor. The values of exchange energy, double exchange model, hybridization of p-d states, and exchange constants are calculated to explore the nature of ferromagnetism and spin functionality. The effect of thermoelectric parameters on spin of electrons and thermoelectric performance are elaborated by thermal to electrical conductivity ratio, Seebeck coefficient and power factor. • High Curie temperature, and spintronic applications. • Spin of electrons overcome the charge with multifuctional properties. • Double exchange mechanism confirms the ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism and 100 % spin polarization. • Large value of electrical conductivity and low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

In the present work, theoretical investigations of structural, electronic, magnetic, and thermoelectric properties of Cd 0.875 TM 0.125 O (TM = Mn, Fe, Co, Ni) half-metallic ferromagnets are done using WIEN2K code. The computed results when compared with the reported theoretical works reveal consistency. The band structures for spin up (↑), and spin down (↓) channels reveal the half metallic (Mn, Co, Fe), and frustrated (Ni) magnetism. The nature of magnetism has been analyzed in terms of hybridization among 3d states of TMs, individual Cd (5s, 4d) states, and O (2p) states. The control and function of the electron spin are revealed by calculating exchange energies (Δ x (d), Δ x (pd)), crystal field energy (ΔE cryst) and exchange constant (N o α, N o β), those play a very crucial role in understanding the magnetic nature. Moreover, double exchange and RKKY models are discussed to justify the observed half-metallic, and metallic behaviors, which are responsible for the magnetic moments to stabilize a magnetic polarization. The influence of electron spin is explained using the computed electrical and thermal conductivities, while thermoelectric power is elaborated by computing Seebeck coefficient and power factor. • Above room temperature ferromagnetism, and spintronic applications •Quantum spin of electrons dominant the charge with multifuctional properties •Exchange mechanism certifies the ferromagnetism by electron spin instead of magnetic ion clustering •Half metallic ferromagnetism and 100% spin polarization •Large value of electrical conductivity and ultralow low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

Abstract: Spin injection across ferromagnet/organic semiconductor system with finite width of the layers was studied theoretically considering spin-dependent conductivity in the organic-semiconductor. It was found that the spin injection efficiency is directly dependent on the difference between the conductivity of the up-spin and down-spin polarons in the spin-injected organic system. Furthermore, the finite width of the structure, interfacial electrochemical-potential and conductivity mismatch have great influence on the spin injection process across ferromagnet/organic semiconductor interface. [Copyright &y& Elsevier]

The simultaneous existence of magnetic order and semiconducting nature in ferromagnetic semiconductors fascinate the spintronics technology to enhance the quantum computing and spin transistors. Therefore, electrons spin dependent ferromagnetism and thermoelectric properties of MgCr 2 X 4 (X ​= ​S, Se) spinels are scrutinized by density functional theory (DFT) based Wien2k code. The negative formation energy ensures thermodynamic stability. The band structures (BS) and density of states (DOS) ensure the ferromagnetic semiconductors nature of the studied spinel's. The insulating behavior in down spin and magnetic moment (Integer value) is the response of 100% spin polarization. The fulfillment of the condition Δ (d) > (Δ C F) and negative Δ (p d) have showed the dominant role of electrons spin to induce ferromagnetism. Moreover, influence of electrons spin on thermodynamic and thermoelectric characteristics are explored by specific heat capacity (C v), electrical conductivity (σ/τ), thermal conductivity ((κ/τ)), Seebeck coefficient (S) and power factor (σS2) by classical Boltzmann transport theory. The Ferromagnetic Semiconducting behavior of MgCr 2 X 4 (X ​= ​S, Se) in which up spin channel is semiconducting and down spin channel is insulating. Image 1 • The MgCr 2 X 4 (X ​= ​S, Se) spinels are ferromagnetic semiconductors with 100% spin polarization. • The exchange energies are exactly according to double exchange mechanism. • The above room temperature ferromagnetism enhance the potential for spintronics. • The thermal conductivity and electrical conductivity ratio is of the order of 10−5. [ABSTRACT FROM AUTHOR]

Band strucutre (BS) plots (a) Ca 0.75 Ti 0.25 S and (b) Ca 0.75 Ti 0.25 Se calcuated by using mBJ potnetial. • The Ca 0.75 Ti 0.25 S and Ca 0.75 Ti 0.25 Se are half metallic ferromagnetism with 100% spin polarization. • The exchange energies are exactly according to double exchange mechanism. • The above room temperature ferromagnetism enhance the potential for spintronics. • The thermal conductivity and electrical conductivity ratio is of the order of 10−4. The electronic, magnetic and thermoelectric properties of Ca 0.75 Ti 0.25 S and Ca 0.75 Ti 0.25 Se alloys are explored comprehensively. The stabilityin ferromagnetic state (FM) has been ensured by energy released from optimized structures and enthalpy of formation (ΔH). The Heisenberg classical model has been used to calculate Curie temperature (T c). The band structures (BS) as well as densities of states (DOS) are analyzed to explore half metallic ferromagnetism and 100% spin polarization. The Δ x (d) (exchange energy) overcome ΔE crystal (Crystal field energy) due to ferromagnetism induced by strong hybridization. The negative values of Δ x (pd) and exchange constant N 0 β lesser exchange energy which satisfy the double exchange model. The thermoelectric properties of the studied compounds are elaborated in terms of electrical conductivity, thermal conductivity and Seebeck coefficient. The increase in power factor with the replacement of S by Se has been noted. [ABSTRACT FROM AUTHOR]