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تسجيل مستخدم جديدImprovement and protection of niobium surface superconductivity by Atomic Layer Deposition and heat treatment
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T. Proslier
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A method to treat the surface of Nb is described which potentially can improve the performance of superconducting RF cavities. We present tunneling and x-ray photoemission spectroscopy (XPS) measurements at the surface of cavity-grade niobium samples coated with a 3 nm alumina overlayer deposited by Atomic Layer Deposition (ALD). The coated samples baked in ultra high vacuum (UHV) at low temperature reveal at first degraded superconducting surface. However, at temperatures above 450C, the tunneling conductance curves show significant improvements of the superconducting density of states (DOS) compared with untreated surfaces.
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Atomic Layer Deposition (ALD) is a promising technique for producing Josephson junctions (JJs) with lower defect densities for qubit applications. A key problem with using ALD for JJs is the interfacial layer (IL) that develops underneath the tunnel
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