Pressure-induced multicriticality and electronic instability in the quasi-kagome ferromagnet URhSn

We report an unconventional class of pressure-induced quantum phase transitions, possessing two bicritical points at 6.25 GPa in URhSn. This unique transformation accompanies a Fermi surface reconstruction, demarcating competing ordered phases suitably described with a localized and itinerant description of the magnetic $5f$ electrons. Ferromagnetic fluctuations over a wide range of temperatures and pressures in the pressure-induced low temperature phase are evidenced by a robust ${T}^{5/3}$ temperature dependence of resistivity up to 11 GPa, which is a characteristic of an elusive marginal Fermi-liquid state.