Synthesis and Characterization of Thin Films of the Quantum Spin Liquid Candidate Tb₂Ti₂O₇

Quantum spin liquids, exotic magnetic materials where spins fluctuate down to the lowest temperatures, are predicted to host fractionalized excitations and emergent gauge fields and are a potential platform for next-generation quantum computing. The thin film geometry offers potential advantages in quantum spin liquid synthesis and future device fabrication. Using reactive-oxide molecular beam epitaxy, we synthesize thin films of the rare-earth titanate pyrochlore Tb₂Ti₂O₇. We probe the impact of defects on the magnetic behavior of this enigmatic quantum spin liquid candidate with STEM imaging and SQUID magnetometry. We find that changing the film composition allows us to control the formation of extended defects which reduce the magnetic frustration in off-stoichiometry films.<br/><br/>This work was supported by the Air Force Office of Scientific Research (MURI Grant No. FA9550-21-1-0429).