title: Field-induced magnetic instability and quantum criticality in the antiferromagnet CeCu2Ge2.
abstract: The magnetic quantum criticality in strongly correlated electron systems has been considered to be closely related with the occurrence of unconventional superconductivity. Control parameters such as magnetic field, pressure or chemical doping are frequently used to externally tune the quantum phase transition for a deeper understanding. Here we report the research of a field-induced quantum phase transition using conventional bulk physical property measurements in the archetypal antiferromagnet CeCu2Ge2, which becomes superconductive under a pressure of about 10 GPa with Tc ~ 0.64 K. We offer strong evidence that short-range dynamic correlations start appearing above a magnetic field of about 5 T. Our demonstrations of the magnetic instability and the field-induced quantum phase transition are crucial for the quantum criticality, which may open a new route in experimental investigations of the quantum phase transition in heavy-fermion systems.
authors.affiliation: Science and Technology on Surface Physics and Chemistry Laboratory, P.O.Box 718-35, Mianyang 621907, P.R.China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Science and Technology on Surface Physics and Chemistry Laboratory, P.O.Box 718-35, Mianyang 621907, P.R.China.
authors.forename: Donghua
authors.initials: D
authors.lastname: Xie
authors.affiliation: Science and Technology on Surface Physics and Chemistry Laboratory, P.O.Box 718-35, Mianyang 621907, P.R.China.
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Wang
authors.affiliation: Science and Technology on Surface Physics and Chemistry Laboratory, P.O.Box 718-35, Mianyang 621907, P.R.China.
authors.forename: Kangwei
authors.initials: K
authors.lastname: Zhu
authors.affiliation: Science and Technology on Surface Physics and Chemistry Laboratory, P.O.Box 718-35, Mianyang 621907, P.R.China.
authors.forename: Ruilong
authors.initials: R
authors.lastname: Yang