Specific heat of CeRhIn5: Pressure-driven transition from antiferromagnetism to heavy-fermion superconductivity
Published Web Locationhttps://doi.org/10.1016/S0921-4534(02)02364-X
CeRhIn5 is known to show an unusual transition at a critical pressure of ∼15 kbar. Specific-heat data show a gradual change in the zero-field "magnetic" specific-heat anomaly from one typical of antiferromagnetic (AF) ordering at ambient pressure to one more characteristic of a Kondo singlet ground state at 21 kbar. However, at 15 kbar there is a discontinuous change from an AF ground state to a superconducting ground state, and evidence of a weak thermodynamic first-order transition. Above the critical pressure, the low-energy excitations are characteristic of superconductivity with line nodes in the energy gap, and, at intermediate pressures, of extended gaplessness. © 2003 Elsevier Science B.V. All rights reserved.