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arXiv · 1411.4815

Molybdenum-Rhenium alloy based high-$Q$ superconducting microwave resonators

Abstract

Superconducting microwave resonators (SMR) with high quality factors have become an important technology in a wide range of applications. Molybdenum-Rhenium (MoRe) is a disordered superconducting alloy with a noble surface chemistry and a relatively high transition temperature. These properties make it attractive for SMR applications, but characterization of MoRe SMR has not yet been reported. Here, we present the fabrication and characterization of SMR fabricated with a MoRe 60-40 alloy. At low drive powers, we observe internal quality-factors as high as 700,000. Temperature and power dependence of the internal quality-factors suggest the presence of the two level systems from the dielectric substrate dominating the internal loss at low temperatures. We further test the compatibility of these resonators with high temperature processes such as for carbon nanotube CVD growth, and their performance in the magnetic field, an important characterization for hybrid systems.

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Vibhor Singh, Ben H. Schneider, Sal J. Bosman, Evert P. J. Merkx, Gary A. Steele. 2014-11-18. Molybdenum-Rhenium alloy based high-$Q$ superconducting microwave resonators. https://doi.org/10.1063/1.4903042

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