Spin fluctuations near a spin-density-wave instability in periodic Anderson model studied by two-particle approach in dynamical mean field theory

We study the magnetic properties of periodic Anderson model when the system approaches to the vicinity of a spin-density-wave(SDW) instability from paramagnetic phase. Static and dynamical $Q$-dependent susceptibility are calculated using a two-particle approach in dynamical mean field theory. The SDW instability at a critical value of hybridyztion $V_c$ is identified by the divergence of static susceptibility at low temperature and at a wavevector $Q_c$ which connects the ``hot zones'' of the conduction band. Away from $V_c$, spin fluctuations at $Q_c$ is suppressed at low energy and at low temperature in the heavy Fermi liquid regime, while near $V_c$, spin fluctuations at $Q_c$ are significantly enhanced as temperature decreases. This indicates that the SDW instability is due to the competition between RKKY interaction and Kondo coupling in the crossover regime.