Scanning laser microscopy of an MgB2 superconducting sensor

Abstract The MgB 2 detector consists of a 200-nm-thick MgB 2 thin-film meander line, a 300-nm-thick SiO protective layer, and 150-nm-thick Nb electrodes. We prepared a straight MgB 2 stripline of width 3 μm and length 100 μm. To understand the position-dependent sensitivity of the MgB 2 detector, a scanning pulsed laser spot can be achieved by the combination of the XYZ piezo-drive stages and an optical fiber with an aspheric focusing lens. The observed scanning XY image indicates that the improvement in sensor homogeneity is very important to improve the sensitivity of the MgB 2 sensor as a neutron detector.