Hybridization gap inCe3Bi4

M. F. Hundley

¹

,

P. C. Canfield

²

,

J. D. Thompson

³

et al.

Abstract

We present resistivity p(T), susceptibility Z(T), and specific heat C(T) data for CeiBi4Pti.The susceptibility exhibits a broad maximum centered near 80 K, typical of a somewhat-heavyelectron compound; were the material metallic, a linear coefficient of specific heat y 75 mJ/molCeK would be expected. However, the compound is not metallic, as indicated by its resistivity which rises to large values at low temperatures and exhibits activated behavior with an activation energy tt/ktt 35 K. By analogy to SmB6 and YbB|p this energy gap arises from 4felectron-conduction-electron hybridization.Due to the gap, electronic excitations are suppressed at low temperatures and the specific heat is smaller than in nonmagnetic La38i4Pt3. Alloying with lanthanum ((Cei-"La,)iBi4Pt&) decreases the resistivity and increases the specific heat towards the value expected for the metallic case; i.e. , for moderate alloying (x 0.07) the behavior is that of a moderately disordered heavy-electron metal. We argue that lattice periodicity is an essential requirement for the formation of the hybridization gap.

In-gap collective mode spectrum of the topological Kondo insulatorSmB6

“…Given that it has some momentum dependence, it is not clear how to find the best substitution by the phenomenological constantsŪ nn ′ . These constants have the units of a 3 2 ×energy and their order of magnitude is set by the hybridization energy scale V 0 . We will indirectly fit the values ofŪ nn ′ in our numerical calculations by trying to match the theoretical collective mode dispersion to the experimentally observed one.…”

“…Kondo insulators are "heavy fermion" materials whose quasiparticle excitations have band-insulating dynamics [1][2][3][4][5][6][7][8][9][10][11] . The most studied Kondo insulator is samarium hexaboride (SmB 6 ), but other similar materials are also known (e.g.…”

Gap-like magnetic excitation in the neutron-scattering response of Ce3Bi4Pt3

“…Ce3Bi4Pt3 appears to be intermediate valence and belongs to the insulating group [ 1 ]. The static susceptibility Xst~t is typical for an intermediate valence compound, i.e.…”

Ce3Bi4Pt3 and hybridization Gap physics

“…This viewpoint provides a rationale for the search for further such materials. Our discussion will be made against the experimental background of Ce3Bi4Pt3, a hybridization gap compound whose properties we have been investigating [2]. Ce3Bi4Pt3 crystallizes in a filled-up variant of the cubic ThsP 4 structure, a structure first reported by Dwight for Y3Sb4Au3 [3].…”