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تسجيل مستخدم جديدMicro(point)contact spectroscopy of dilute magnetic (Kondo) alloys CuMn and CuFe
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The method of microcontact spectroscopy is used to study alloys with magnetic impurities CuMn and CuFe in the range of concentrations 0.01-1 at.%. Minima or maxima (so-called zero-bias anomalies) were observed in the microcontact spectra of these alloys at voltages ~ 1 mV. The Lande g-factor for the Mn impurity in a Cu matrix was determined from the splitting of the minimum of the zero-bias anomaly in a magnetic field. The quantitative calculations carried out agree well with theory and permit determining both the important geometric contact parameter <K> i.e., the averaged geometric form factor, and the characteristics of the alloy itself, for example, J/E_F, i.e., the ratio of the magnitude of the exchange interaction energy between an electron and the magnetic impurity to the Fermi energy, from the microcontact spectra.
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