Field dependence of antiferromagnetic spin fluctuations in the heavy fermion superconductor CeCoIn$_5$

Magnetic fields are proposed as a tuning parameter for quantum critical fluctuations in the heavy fermion superconductor CeCoIn$_5$, with a critical point close to the superconducting $B_{c2}$. Here, $^{59}$Co NMR spin lattice relaxation is used to study the effect of magnetic field applied on the amplitude, dimensionality, and anisotropy of antiferromagnetic spin fluctuations for temperatures covering $T$=100mK-100K and $B=$5-10T ($\parallel {\mathbf c}$). Spin fluctuations are evident for temperatures below $T\sim40$K, below which $[T_1T]^{-1}$ increases markedly for all fields. At lower temperatures, a significant dependence on magnetic field is observed. For fields $B>B_{c2}=$5T, $[T_1T]^{-1}\to$constant for $T

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2010.MAR.J38.5