Strange metal near antiferromagnetic instability and Kondo breakdown in heavy-fermion systems.

The strange metal behavior with T-linear resistivity and T-logarithmic specific heat coefficient has been widely observed in heavy-fermion metals close to antiferromagnetic transitions. The underlying mechanism leading to this behavior constitutes an outstanding and largely unresolved issue. An increasing amount of experiments indicates a link to a Kondo breakdown quantum critical point. To investigate this, we study the 2D Kondo-Heisenberg model via a dynamical large-N multichannel Schwinger boson approach. We identify and characterize the quantum critical point separating the antiferromagnetically ordered from the Kondo-screened heavy Fermi-liquid phases. In addition, we find strange-metal behavior in the finite temperature phase diagram close to the transition which agrees qualitatively with the experimental results on CeCu_{6-x}Au_{x}, YbRh_{2}Si_{2}, and others.