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تسجيل مستخدم جديدMerged-Element Transmons: Design and Qubit Performance
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We have demonstrated a novel type of superconducting transmon qubit in which a Josephson junction has been engineered to act as its own parallel shunt capacitor. This merged-element transmon (MET) potentially offers a smaller footprint and simpler fabrication than conventional transmons. Because it concentrates the electromagnetic energy inside the junction, it reduces relative electric field participation from other interfaces. By combining micrometer-scale Al/AlOx/Al junctions with long oxidations and novel processing, we have produced functional devices with $E_{J}$/$E_{C}$ in the low transmon regime ($E_{J}$/$E_{C}$ $lesssim$30). Cryogenic I-V measurements show sharp dI/dV structure with low sub-gap conduction. Qubit spectroscopy of tunab
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