Thermodynamic, Transport, and Excitation Properties of Ce Impurities in a Model Metal: Kondo Resonance and Universality in the Mixed-Valent Regime

Thermoelectric power of the YbT2Zn20(Mun1, Jia2, Bud’ko3 et al. 2012Phys. Rev. B201130View full textAdd to dashboardCite

“…When T K < ∆/k B , more than one peak has been frequently observed in the TEP [25,[30][31][32]. The low temperature extremum is usually located close to T K , and the high temperature extremum located at 0.4-0.6 ∆/k B is attributed to Kondo scattering off of the thermally populated CEF levels, which is in agreement with theoretical predictions [2,4,[33][34][35][36]. Therefore, the peak position can represent T K and ∆/k B as relevant energy scales in Kondo lattice systems.…”

Unusual Electron Transport Properties of U0.05Y0.95Al2

“…1b we show the thermoelectric power of U 0.05 Y 0.95 Al 2 measured by a differential method. The alloy displays a Kondo-like increase at elevated temperature range and a positive maximum of about 13 µV/K at T max = 42 K. It should be mentioned that a similar S(T ) behaviour has been observed for a number of Ce-based Kondo systems [9], and can be explained with the help of the single- -impurity Kondo effect model [10,11]. Accordingly to the model, a maximum with large magnitude is expected to locate around the characteristic temperature of the order of the Kondo temperature T K .…”

Deposition and investigation of lanthanum–cerium hexaboride thin films

“…r(T) of films show typical metallic behavior. Resistivity of some films decreases monotonically down to the temperature $20 K and then practically does not change down to 4 K. Such a behavior of r(T) is typical for the LaB 6 system [4] and is a feature of absence of the Kondo effect. Parameter of metallicity r(77 K)/r(300 K) of these films is 40.77 and the resistivity values of films r(300 K)X100 mO cm.…”

“…Lanthanum hexaboride with a cerium impurity ($1%) is a Kondo system with a number of anomalies of kinetic properties at low temperatures. So, in the works [1][2][3][4] concerning investigation of bulk samples of (La,Ce)B 6 , anomalous behavior of the electrical conductivity [1,2], a peak in the heat capacity and thermopower [3,4] at low temperatures, were observed. The values of the Seebeck coefficient given in [3,4] (S$80 mV/K at T$1 K) and the corresponding evaluations of the figure of merit, Z$0.47 [5], allow one to consider (La,Ce)B 6 as a promising material for creation of thermoelectric refrigerators and thermoelectric detectors in the UV and X-ray ranges [6,7].…”

“…So, in the works [1][2][3][4] concerning investigation of bulk samples of (La,Ce)B 6 , anomalous behavior of the electrical conductivity [1,2], a peak in the heat capacity and thermopower [3,4] at low temperatures, were observed. The values of the Seebeck coefficient given in [3,4] (S$80 mV/K at T$1 K) and the corresponding evaluations of the figure of merit, Z$0.47 [5], allow one to consider (La,Ce)B 6 as a promising material for creation of thermoelectric refrigerators and thermoelectric detectors in the UV and X-ray ranges [6,7]. There are no data in the literature concerning the deposition of (La,Ce)B 6 films, therefore, in our studies, we considered as a base the works on obtaining the LaB 6 films synthesized mainly by the methods of the electronbeam [8,9] and magnetron [10,11] deposition.…”