Non fermi liquid ground states in strongly correlated f-electron materials

Experimental efforts to characterize and develop an understanding of non Fermi liquid (NFL) behavior at low temperature in f-electron materials are reviewed for three f-electron systems: M1−xUxPd3 (M = Sc, Y), U1−xThxPd2Al3, and UCu5−xPdx. The emerging systematics of NFL behavior in f-electron systems, based on the present sample of nearly ten f-electron systems, is updated. Many of the f-electron systems exhibit the following temperature dependences of the electrical resistivity p, specific heat C, and magnetic susceptibility χ for T ≪ T0, where To is a characteristic temperature: P(T) ∼ 1 –aT/T0, where a 0, C(T)/T ∼ (-1/To) In (T/bT0), and χ(T) ∼ 1 −c(T/To)1/2. In several of the f-electron systems, the characteristic temperature To can be identified with the Kondo temperature Tk.