Critical Phenomena in Frustrated Pyrochlore Magnets

The study of magnetically frustrated systems is crucial for understanding exotic ground states and emergent phenomena, such as Kitaev spin liquid states and two-dimensional magnetic monopole gases. The pyrochlore frustrated magnets, R₂​Ir₂​O_7, R₂Ti₂​O₇ (R = Dy, Ho), and their alloys​, serve as an excellent platform to explore frustrated behavior due to their ability to transition into various states driven by the local interactions of iridate moments. This necessitates a systematic investigation of observables such as entropy, specific heat, and magnetic susceptibility. In this work, we studied these observables in pyrochlore frustrated magnets using Monte Carlo simulation and found two distinct critical phases at the boundaries between different frustration phases. These critical phases are characterized by significantly high entropy and a lack of magnetic order, in contrast to the spin ice phase, fragmented phase, and antiferromagnetic state of pyrochlore frustrated magnets​. The scaling behavior of these observables are studied to provide insights into the frustrated phase transitions. The unique nature of excitations in these critical phases opens avenues for tunable field-induced and dynamical behaviors, expanding the horizon of magnetic phenomena in frustrated systems.