Anomalous Magnetoresistance by Breaking Ice Rule in Bi₂Ir₂O₇/ Dy₂Ti₂O₇ Heterostructure

Pyrochlore Dy₂Ti₂O₇ is one of the most well-known spin ice prototypes that has attracted much attention due to its extensively degenerate ground state, emergent monopole excitations and coulomb phase. The ice rule can be broken when raising the temperature or applying a magnetic field along a [1,1,1] direction. The latter is known to drive the spin ice state into a 3-in-1-out state evidenced by a quantized magnetization increment. In this talk, we will discuss our recent work on synthesizing epitaxial pyrochlore heterostructures Bi₂Ir₂O₇/Dy₂Ti₂O₇. Bi₂Ir₂O₇ is a paramagnetic correlated metal of the pyrochlore iridate series and in proximity to a quantum critical point of an all-in-all-out state. Systematic transport measurements show that the correlated charge carriers in Bi₂Ir₂O7 are highly sensitive to spin fluctuations due to breaking of the ice rule in Dy₂Ti₂O₇, resulting in anomalous magnetoresistance. Our work demonstrates the possibility of “metallizing” insulating quantum magnets through epitaxial interfaces.