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تسجيل مستخدم جديدMagnetic properties of defect-free and oxygen-deficient cubic SrCoO$_{3-delta}$
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We investigated theoretically electronic and magnetic properties of the perovskite material SrCoO$_{3-delta}$ with $deltaleq 0.15$ using a projector-augmented plane-wave method and a Greens function method. This material is known from various experiments to be ferromagnetic with a Curie temperature of 260$,$K to 305$,$K and a magnetic moment of 1.5${,mu_text{B}}$ to 3.0${,mu_text{B}}$. Applying the magnetic force theorem as it is formulated within Greens function method, we calculated for SrCoO$_{3-delta}$ the magnetic exchange parameters and estimated the Curie temperature. Including correlation effects by an effective $U$ parameter within the GGA$+U$ approach and verifying this by hybrid functional calculations, we obtained the Curie temperatures in dependence of the oxygen deficiency close to the experimental values.
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It has been well established that both in bulk at ambient pressure and for films under modest strains, cubic SrCoO$_{3-delta}$ ($delta < 0.2$) is a ferromagnetic metal. Recent theoretical work, however, indicates that a magnetic phase transition to a
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We present the first-principles investigation of the structural, electronic, and magnetic properties of SrCoO$_{3-delta}$ ($delta=0, 0.25, 0.5$) to understand the multivalent nature of Co ions in SrCoO$_{3-delta}$ along the line of topotactic transit
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