14,617 research outputs found

    Simultaneous observation of small- and large-energy-transfer electron-electron scattering in three dimensional indium oxide thick films

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    In three dimensional (3D) disordered metals, the electron-phonon (\emph{e}-ph) scattering is the sole significant inelastic process. Thus the theoretical predication concerning the electron-electron (\emph{e}-\emph{e}) scattering rate 1/τφ1/\tau_\varphi as a function of temperature TT in 3D disordered metal has not been fully tested thus far, though it was proposed 40 years ago [A. Schmid, Z. Phys. \textbf{271}, 251 (1974)]. We report here the simultaneous observation of small- and large-energy-transfer \emph{e}-\emph{e} scattering in 3D indium oxide thick films. In temperature region of T≳100T\gtrsim100\,K, the temperature dependence of resistivities curves of the films obey Bloch-Gr\"{u}neisen law, indicating the films possess degenerate semiconductor characteristics in electrical transport property. In the low temperature regime, 1/τφ1/\tau_\varphi as a function of TT for each film can not be ascribed to \emph{e}-ph scattering. To quantitatively describe the temperature behavior of 1/τφ1/\tau_\varphi, both the 3D small- and large-energy-transfer \emph{e}-\emph{e} scattering processes should be considered (The small- and large-energy-transfer \emph{e}-\emph{e} scattering rates are proportional to T3/2T^{3/2} and T2T^2, respectively). In addition, the experimental prefactors of T3/2T^{3/2} and T2T^{2} are proportional to kFβˆ’5/2β„“βˆ’3/2k_F^{-5/2}\ell^{-3/2} and EFβˆ’1E_F^{-1} (kFk_F is the Fermi wave number, β„“\ell is the electron elastic mean free path, and EFE_F is the Fermi energy), respectively, which are completely consistent with the theoretical predications. Our experimental results fully demonstrate the validity of theoretical predications concerning both small- and large-energy-transfer \emph{e}-\emph{e} scattering rates.Comment: 5 pages and 4 figure

    The tensor renormalization group study of the general spin-S Blume-Capel model

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    We focus on the special situation of D=2JD=2J of the general spin-S Blume-Capel model on the square lattice. Under the infinitesimal external magnetic field, the phase transition behaviors due to the thermal fluctuations are discussed by the newly developed tensor renormalization group method. For the case of the integer spin-S, the system will undergo SS first-order phase transitions with the successive symmetry breaking with the magnetization M=S,Sβˆ’1,...0M=S,S-1,...0. For the half-integer spin-S, there are similar Sβˆ’1/2S-1/2 first order phase transition with M=S,Sβˆ’1,...1/2M=S,S-1,...1/2 stepwise structure, in addition, there is a continuous phase transition due to the spin-flip Z2Z_2 symmetry breaking. In the low temperature regions, all first-order phase transitions are accompanied by the successive disappearance of the optional spin-component pairs(s,βˆ’ss,-s), furthermore, the critical temperature for the nth first-order phase transition is the same, independent of the value of the spin-S. In the absence of the magnetic field, the visualization parameter characterizing the intrinsic degeneracy of the different phases clearly demonstrates the phase transition process.Comment: 6 pages, 7 figure
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