Effect of Nd and Rh substitution on the spin dynamics of the Kondo-insulator CeFe2Al10
| Autor: | T. Takabatake, Paul Steffens, Stéphane Rols, V. N. Lazukov, Jean-Michel Mignot, Hiroshi Tanida, Yuji Muro, Masafumi Sera, P. A. Alekseev, D. T. Adroja |
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| Rok vydání: | 2020 |
| Předmět: |
Materials science
Kondo insulator Resonance 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Crystallography Impurity 0103 physical sciences Condensed Matter::Strongly Correlated Electrons Orthorhombic crystal system Crystallite 010306 general physics 0210 nano-technology Spin (physics) Single crystal Energy (signal processing) |
| Zdroj: | Physical Review B. 102 |
| ISSN: | 2469-9969 2469-9950 |
| Popis: | The dynamic magnetic properties of the Kondo-insulator state in $\mathrm{Ce}{\mathrm{Fe}}_{2}{\mathrm{Al}}_{10}$ (spin gap, resonance mode) have been investigated using polarized neutrons on a single crystal of pure $\mathrm{Ce}{\mathrm{Fe}}_{2}{\mathrm{Al}}_{10}$. The results indicate that the magnetic excitations are polarized mainly along the orthorhombic $a$ axis and their dispersion along the orthorhombic $c$ direction could be determined. Polycrystalline samples of Nd- and Rh-doped $\mathrm{Ce}{\mathrm{Fe}}_{2}{\mathrm{Al}}_{10}$ were also studied by the time-of-flight technique, with the aim of finding out how the low-energy magnetic excitation spectra change upon isoelectronic substitution of a rare-earth element (Nd) on the magnetic Ce site or electron doping (Rh) on the transition-element Fe sublattice. The introduction of magnetic Nd impurities strongly modifies the spin gap in the Ce dynamic magnetic response and causes the appearance of a quasielastic signal. The crystal-field excitations of Nd, studied in both $\mathrm{La}{\mathrm{Fe}}_{2}{\mathrm{Al}}_{10}$ and $\mathrm{Ce}{\mathrm{Fe}}_{2}{\mathrm{Al}}_{10}$, also reveal a significant influence of $f$-electron hybridization (largest in the case of Ce) on the crystal-field potential. As a function of the Rh concentration, a gradual change is observed from a Kondo-insulator to a metallic Kondo-lattice response, likely reflecting the decrease in the hybridization energy. |
| Databáze: | OpenAIRE |
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