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    Studies on the heavy-fermion pyrochlore iridate (Pr$_2$Ir$_2$O$_7$) point to the role of time-reversal-symmetry breaking in geometrically frustrated Kondo lattices. With this motivation, here we study the effect of Kondo coupling and chiral spin liquids in a frustrated $J_1-J_2$ model on a square lattice. We treat the Kondo effect within a slave-fermion approach, and discuss our results in the context of a proposed global phase diagram for heavy fermion metals. We calculate the anomalous Hall response for the chiral states of both the Kondo destroyed and Kondo screened phases. Across the quantum critical point, a reconstruction of the Fermi surface leads to a sudden change of the Berry curvature distribution and, consequently, a jump of the anomalous Hall conductance. We discuss the implications of our results for the heavy-fermion pyrochlore iridate and propose an interface structure based on Kondo insulators to further explore such effects.
    Kondo insulator
    Citations (2)
    We discuss the magnetic phases in the periodic Anderson model and determine the conditions under which there appears a stable Fermi-liquid state with (i) small antiferromagnetic moment of $f$ electrons, largely compensated by the conduction electrons, (ii) high density of states at the Fermi level, and (iii) almost integer occupation of the $f$ level. We use a modified version of the spin rotationally invariant slave-boson approach, in which a strong nonlinear molecular field acting on $f$ electrons appears already in the saddle-point approximation. For an even number of electrons an antiferromagnetic Kondo insulating state transforms with increasing hybridization into a paramagnetic Kondo insulator.
    Anderson impurity model
    Kondo insulator
    Slave boson
    Density of states
    Strongly correlated material
    Citations (45)