Neutron Scattering Study of the Field Induced Non-Fermi-Liquid Behavior in CeAuSb$_2$

The modestly heavy Fermion compound CeAuSb$_2$ ($\gamma = 90 $~mJ/K$^2$~mol) was reported to exhibit highly anisotropic magnetic properties with an antiferromagnetic transition temperature $T_N \approx 5$~K~[1]. In addition, the unconventional temperature dependence of the resistivity and specific heat, observed when an external magnetic field suppresses $T_N$ to 0~K, has lead to the identification of CeAuSb$_2$ as a system showing possible magnetic field-induced quantum critical behavior [2]. Here we report on neutron scattering measurements of CeAuSb$_2$ in magnetic fields up to 9~T applied along the $\left$ direction. Both elastic and inelastic measurements were carried out to track the evolution of the magnetic structure and spin fluctuations as a function of applied field. \\[4pt] [1] A. Thamizhavel et al., Phys. Rev. B \textbf{68}, 054427 (2003).\\[0pt] [2] L. Balicas et al., Phys. Rev. B \textbf{72}, 064422 (2005).