Discovery of Magnetic Phase Transitions in Heavy-Fermion Superconductor CeRh_{2}As_{2}.

We report on the specific heat studies performed on a new generation of CeRh_{2}As_{2} single crystals. Superior quality of the samples and dedicated experimental protocol allowed us to observe an antiferromagneticlike behavior in the normal state and to detect the first-order phase transition of magnetic origin within the superconducting state of the compound. Although in the available literature the physical behavior of CeRh_{2}As_{2} is most often described with the use of quadrupole density wave scenario, we propose an alternative explanation using analogies to antiferromagnetic heavy-fermion superconductors CeRhIn_{5} and Ce_{2}RhIn_{8}.

Horizontal flux growth as an efficient preparation method of CeRh2As2 single crystals.

We report an efficient method to obtain CeRh2As2 single crystals with the use of a bismuth flux growth method in a horizontal configuration. Based on our numerous attempts, we found this technique to be scalable and repeatable. The crystals thus obtained are characterized by much sharper phase transitions and distinctly higher characteristic temperatures Tc and T0, compared to previous reports. Moreover, based on our specific heat studies of the obtained single crystals, we also indicate a clear connection between both transition temperatures.