Analytical expressions for the effective mass of heavy, light, and spin split-off electrons are obtained by diagonalizing the k⋅p Hamiltonian for cubic perovskite crystal structures and used to calculate these in nine perovskite materials. An expression for the effective hole g-factor is also derived and calculated in these perovskites. The calculated effective mass of heavy electrons ranges from 1.619 m0 to 0.201 m0, of light electrons from 0.357 m0 to 0.146 m0, and of spin split-off electrons from 0.584 m0 to 0.169 m0. It is found that Cl- and Pb-based perovskite materials have larger heavy, light, and spin split-off electron effective masses. It is also found that the effective g-factor increases with the atomic size, from Cl to I, for the series CsSnX3(X=Cl,Br,I).

Electron transport through nanodevices of atoms in a single-layer rectangular arrangement with free (open) boundary conditions parallel to the direction of the current flow is studied within the singleband tight binding model. The Landauer formula gives the electrical conductance to be a function of the electron transmission probability, ( ) E , as a function of the energy E of the incoming electron. A quantum dragon nanodevice is one which has a perfectly conducting channel, namely  = ( ) E 1 for all energies which are transmitted by the external leads even though there may be arbitrarily strong electron scattering. The rectangular single-layer systems are shown to be able to be quantum dragon devices, both for uniform leads and for dimerized leads. The quantum dragon condition requires appropriate lead-device connections and correlated randomness in the device. F .

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This research study was aimed at determining the temperature dependence of Ferromagnetic Resonance (FMR), the recorded signal versus angle and the magnetic property of the 15 uc thick La 0.7 Sr 0.3 MnO 3 (LSMO) thin film sample on a single crystalline SrTiO 3 (STO) substrate at 150 K and 9.75 GHz using ferromagnetic resonance technique. We observed from the Ferromagnetic Resonance (FMR) spectra at various temperatures (150, 200 and 250 K, respectively) that as the temperature increases, the FMR spectra shifts to higher fields and this might be as a result of transition into the ferromagnetic state. The recorded signal versus the angle showed an unusual phenomenon at all temperatures (150, 200 and 250 K, respectively) and this might be due to shape effects and other contributing factors such as misfit strain and crystal misfit in the LSMO thin film. The plot of resonance field versus the in-plane angle showed a spectrum which was sinusoidal-like in nature with maximum and minimum curvatures. The resonance position and the Full Width Half Maximum (FWHM) of the 15 uc thick LSMO thin film were 718.15 and 561.45 Oe, respectively. The 15 uc thick LSMO thin film displayed ferromagnetic resonance at 150, 200 and 250 K, respectively and this has been confirmed using the surface plot.

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