Abstract
Applied pressure drives the heavy-fermion antiferromagnet CeRhIn5 toward a quantum critical point that becomes hidden by a dome of unconventional superconductivity. Magnetic fields suppress this superconducting dome, unveiling the quantum phase transition of local character. Here, we show that [Formula: see text] magnetic substitution at the Ce site in CeRhIn5, either by Nd or Gd, induces a zero-field magnetic instability inside the superconducting state. This magnetic state not only should have a different ordering vector than the high-field local-moment magnetic state, but it also competes with the latter, suggesting that a spin-density-wave phase is stabilized in zero field by Nd and Gd impurities, similarly to the case of Ce0.95Nd0.05CoIn5 Supported by model calculations, we attribute this spin-density wave instability to a magnetic-impurity-driven condensation of the spin excitons that form inside the unconventional superconducting state.
Highlights
Applied pressure drives the heavy-fermion antiferromagnet CeRhIn5 toward a quantum critical point that becomes hidden by a dome of unconventional superconductivity
Once Tc exceeds TN at Pc∗1, there is no evidence for magnetism in ρ(T ), and the possibility of Nd-induced magnetism is obscured by the zero-resistance state below Tc
We note that previous investigations of a microscopically motivated theoretical model found that the Q phase may be stabilized by magnetic impurities even at zero external field [37]. These results suggest that other magnetic impurities could induce the same type of Spin-density wave (SDW) order in both CeCoIn5 and pressurized CeRhIn5
Summary
Applied pressure drives the heavy-fermion antiferromagnet CeRhIn5 toward a quantum critical point that becomes hidden by a dome of unconventional superconductivity. Magnetic fields suppress this superconducting dome, unveiling the quantum phase transition of local character. Unconventional superconductivity (SC) frequently is found as an antiferromagnetic (AFM) transition is tuned by chemical substitution or pressure toward a zero-temperature phase transition, a magnetic quantum-critical point. This observation has a qualitative explanation: The proliferation of quantum fluctuations of magnetic origin at low temperatures can trigger the formation of a new ordered state. These observations suggest that the Q phase is the result of a condensation of spin excitations [12, 14, 18]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
