Anisotropic magnetotransport properties of the heavy-fermion superconductor <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>CeRh</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>As</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>
S. Mishra, Yu Liu, E. D. Bauer, F. Ronning, S. M. Thomas
Abstract
We report anisotropic resistivity measurements of the heavy-fermion superconductor ${\mathrm{CeRh}}_{2}{\mathrm{As}}_{2}$ in magnetic fields up to 16 T and temperatures down to 0.35 K. The measured ${\mathrm{CeRh}}_{2}{\mathrm{As}}_{2}$ resistivity shows a signature corresponding to the suggested quadrupole-density-wave order state at ${T}_{0}\ensuremath{\sim}0.5$ K for both measured directions. For a magnetic field applied along the tetragonal $a$ axis, ${T}_{0}$ is enhanced with magnetic field reaching $\ensuremath{\sim}1.75$ K at 16 T. Further, a magnetic field-induced transition occurs at ${\ensuremath{\mu}}_{0}{H}_{m}\ensuremath{\sim}8.1$ T corresponding to a change to a new broken symmetry state. For a magnetic field applied along the $c$ axis, ${T}_{0}$ is suppressed below our base temperature $\ensuremath{\sim}0.35$ K by ${\ensuremath{\mu}}_{0}H\ensuremath{\sim}4.5$ T, a field close to the previously reported field-induced transition within the superconducting state suggested to be from an even-parity to an odd-parity state. Our results indicate that the multiple superconducting phases in ${\mathrm{CeRh}}_{2}{\mathrm{As}}_{2}$ are intimately tied to the suppression of the proposed quadrupole-density-wave phase at ${T}_{0}$.