Lithium niobate’s pyroelectric effect limits quantum device performance

Researchers at the University of Rochester have discovered that the pyroelectric effect in lithium niobate significantly hinders the operation of semiconductor quantum dot devices. Measurements of integrated circuits pairing gallium arsenide/aluminum arsenide and silicon/silicon germanium quantum dots with lithium niobate surface acoustic wave resonators revealed unintended consequences; GaAs/AlGaAs devices experienced unintentional carrier depletion, while Si/SiGe devices suffered electrostatic discharge. The work highlights that “either a non-capacitive coupling mechanism or a non-pyroelectric substrate should be used” for continued progress in quantum interconnects and transducers. Measurements revealed that the pyroelectric effect within lithium niobate actively interfered with the operation of quantum dots integrated into hybrid devices, specifically manifesting as distinct failures depending on the semiconductor material used. These observations stem from experiments involving flip-chip devices designed to capacitively…