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arXiv · 0709.0791

Magneto-optical behaviour of EuIn_2P_2

F. Pfuner·L. Degiorgi. H. R. Ott·A. D. Bianchi·Z. Fisk
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Abstract

We report results of a magneto-optical investigation of the Zintl-phase compound EuIn$_2$P$_2$. The compound orders magnetically at $T_C$=24 K and exhibits concomitant large magnetoresistance effects. For $T\le$50 K and increasing magnetic fields we observe a transfer of spectral weight in $σ_1(ω)$ from energies above 1 eV into the low-energy metallic component as well as into a mid-infrared signal centered at about 600 cm$^{-1}$. This latter absorption is reminiscent to what has been seen in a large variety of so-called Kondo materials and ascribed to excitations across the hybridization gap. The observed gain of Drude weight upon increasing magnetic field suggests an enhancement of the itinerant charge-carrier concentration due to the increasing magnetization, a phenomenon that was previously observed in other compounds which exhibit colossal magnetoresistive effects.

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F. Pfuner, L. Degiorgi. H. R. Ott, A. D. Bianchi, Z. Fisk. 2007-09-06. Magneto-optical behaviour of EuIn_2P_2. https://doi.org/10.1103/physrevb.77.024417

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