Scanning laser microscopy of an MgB2 superconducting sensor

The MgB2 detector consists of a 200-nm-thick MgB2 thin-film meander line, a 300-nm-thick SiO protective layer, and 150-nm-thick Nb electrodes. We prepared a straight MgB2 stripline of width 3 mu m and length 100 mu m. To understand the position-dependent sensitivity of the MgB2 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 MgB2 sensor as a neutron detector. (C) 2010 Published by Elsevier B.V.