Heavy Fermion Fluid in High Magnetic Fields: An Infrared Study ofCeRu4Sb12

Abstract

We report a comprehensive infrared magnetospectroscopy study of a CeRu4Sb12 compound revealing quasiparticles with a heavy effective mass m*, with a detailed analysis of optical constants in fields up to 17 T. We find that the applied magnetic field strongly affects the low-energy excitations in the system. In particular, the magnitude of m* approximately = 70 m(b) (m(b) is the quasiparticle band mass) at 10 K is suppressed by as much as 25% at 17 T. This effect is in quantitative agreement with the mean-field solution of the periodic Anderson model augmented with a Zeeman term.

Electrodynamics of correlated electron materials

“…mir / ffiffiffiffiffi ffi T à p (Garner et al, 2000;Degiorgi et al, 2001;Hancock et al, 2004;Hancock et al, 2006;Okamura et al, 2007). From optical and magneto-optical experiments on numerous nonmagnetic systems, Dordevic, Basov, Dilley et al (2001), Dordevic et al (2006) confirmed the scaling relation m à =m b ¼ ðÁ=k B T Ã Þ 2 between the magnitude of m à and the hybridization gap Á.…”

Optical signatures of momentum-dependent hybridization of the local moments and conduction electrons in Kondo lattices

“…Specifically optical studies have provided experimental access to the hybridization strength via direct observation of the hybridization gap ͑⌬͒ in the dissipative part of the optical conductivity ͓ 1 ͔͑͒. [7][8][9][10][11][12][13][14] These studies have also extensively verified the prediction of the PAM on the scaling between the hybridization gap and the effective mass: ͑ ⌬ T Coh ͒ 2 ϰ m * , where T Coh is the temperature below which coherent scattering between magnetic sites emerges. 8 There have also been recent studies of numerous Yb and Ce compounds, that have demonstrated a scaling between the size of ⌬ and T K , the Kondo temperature.…”

Magnetic, thermal, and electronic properties of iron-antimony filled skutteruditesMFe4Sb12(M=Schnelle1, Leithe‐Jasper2, Rösner3 et al. 2008Phys. Rev. B9611540View full textAdd to dashboardCite

“…Such a field behavior of the gap has actually been observed for the filled skutterudite CeRu 4 Sb 12 by infrared reflectivity measurements. 62 The La y Fe 4 Sb 12 sample displays strongly different exponents ␣ of 1.61-1.68 ͑in zero field͒ and no shoulder at higher temperatures. With increasing field ␣ tends to slightly higher values but the T 2 law is clearly not achieved for the maximum field.…”