Microwave Kinetic Inductance Detector Made of Molecular Beam Epitaxy (MBE)-Grown MgB2 Film

Abstract

We present a MgB2-based Microwave Kinetic Inductance Detector (MKID) featuring a quality factor Qi ~ 105 and noise equivalent power NEP ~ 10−14 W/Hz at 2 K. In comparison to YBCO-based MKIDs, the MgB2 detector shows greater sensitivity to both temperature and magnetic field, a result of its two-gap nature and relatively low critical Hc2 field. Our data indicate that MgB2 is more advantageous for MKID applications at temperatures lower than 3 K.

Keywords

• MBE-grown superconductors
• kinetic inductance detector
• MgB₂