Spin and charge dynamics of the ferromagnetic and antiferromagnetic two-dimensional half-filled Kondo lattice model

Details Spin and charge dynamics of the ferromagnetic and antiferromagnetic two-dimensional half-filled Kondo lattice model Spin and charge dynamics of the ferromagnetic and antiferromagnetic two-dimensional half-filled Kondo lattice model

2000-10-25

arxiv.org/abs/cond-mat/0010393v1

Phys. Rev. B 63, 155114 (2001)

Physics

Condensed Matter

Strongly Correlated Electrons

30 pages, 24 figures

Scientific paper

10.1103/PhysRevB.63.155114

We present a detailed numerical study of spin and charge dynamics of the two-dimensional Kondo lattice model with hopping t and exchange J. At T=0 and J > 0, the competition between the RKKY interaction and Kondo effect triggers a quantum phase transition between magnetically ordered and disordered insulators: J_c/t = 1.45(5). The quasiparticle gap scales as |J|. S(q,\omega), evolves smoothly from its strong coupling form with spin gap at q = (\pi,\pi) to a spin wave form. At J>0, A(\vec{k},\omega) shows a dispersion relation following that of hybridized bands. For J < J_c this feature is supplemented by shadows thus pointing to a coexistence of Kondo screening and magnetism. For J < 0 A(\vec{k},\omega) is similar to that of non-interacting electrons in a staggered magnetic field. Spin, T_S, and charge, T_C, scales are defined. For weak to intermediate couplings, T_S marks the onset of antiferromagnetic fluctuations and follows a J^2 law. At strong couplings T_S scales as J. T_C scales as J both at weak and strong couplings. At and slightly below T_C we observe i) a rise in the resistivity as a function of decreasing temperature, ii) a dip in the integrated density of states at the Fermi energy and iii) the occurrence of hybridized bands in A(k,\omega). It is shown that in the weak coupling limit, the charge gap of order J is of magnetic origin. The specific heat shows a two peak structure, the low temperature peak being of magnetic origin. Our results are compared to various mean-field theories.

Affiliated with

Also associated with

No associations

Rating

Spin and charge dynamics of the ferromagnetic and antiferromagnetic two-dimensional half-filled Kondo lattice model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spin and charge dynamics of the ferromagnetic and antiferromagnetic two-dimensional half-filled Kondo lattice model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spin and charge dynamics of the ferromagnetic and antiferromagnetic two-dimensional half-filled Kondo lattice model will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-105373