Visualizing band selective enhancement of quasiparticle lifetime in a metallic ferromagnet

Abstract

Electrons navigate more easily in a background of ordered magnetic moments than around randomly oriented ones. This fundamental quantum mechanical principle is due to their Bloch wave nature and also underlies ballistic electronic motion in a perfect crystal. As a result, a paramagnetic metal that develops ferromagnetic order often experiences a sharp drop in the resistivity. Despite the universality of this phenomenon, a direct observation of the impact of ferromagnetic order on the electronic quasiparticles in a magnetic metal is still lacking. Here we demonstrate that quasiparticles experience a significant enhancement of their lifetime in the ferromagnetic state of the low-density magnetic semimetal EuCd2As2, but this occurs only in selected bands and specific energy ranges. This is a direct consequence of the magnetically induced band splitting and the multi-orbital nature of the material. Our detailed study allows to disentangle different electronic scattering mechanisms due to non-magnetic disorder and magnon exchange. Such high momentum and energy dependence quasiparticle lifetime enhancement can lead to spin selective transport and potential spintronic applications.

15 pages, 4 figures + supplement

References in corpus (5)

• Two energy gaps and Fermi surface 'arcs' in NbSe2
• Spin fluctuation induced Weyl semimetal state in the paramagnetic phase of EuCd${}_2$As${}_2$
• A Single Pair of Weyl Fermions in Half-metallic EuCd2As2 Semimetal
• Visualizing band selective enhancement of quasiparticle lifetime in a metallic ferromagnet
• Anisotropic physical properties and pressure dependent magnetic ordering of CrAuTe${}_4$

Cited by in corpus (8)

• Spin-carrier coupling induced ferromagnetism and giant resistivity peak in EuCd${}_2$P${}_2$
• Electronic band reconstruction across the insulator-metal transition in colossal magnetoresistive EuCd2P2
• Anisotropic magnetism and electronic structure of trigonal EuAl${}_2$Ge${}_2$ single crystals
• Visualizing band selective enhancement of quasiparticle lifetime in a metallic ferromagnet
• Unusual ferromagnetic band evolution and high Curie temperature in monolayer 1T-CrTe2 on bilayer graphene
• Revealing the EuCd_{2}As_{2} Semiconducting Band Gap via n-type La-Doping
• Recent advances in understanding and manipulating magnetic and electronic properties of Eu$M_2{X}_2$ ($M$ = Zn, Cd; $X$ = P, As)
• Topological phases of electrons induced by electron-magnon interactions