Niobium superconducting strip line detectors (SSLD) for time-of-flight mass spectroscopy (TOF-MS)

Superconducting strip line detectors (SSLDs) have the same nanostructure as so called Superconducting Single Photon Detectors (SSPDs) for ultrafast photon detection. However, the optimum SSLD design for mass spectrometers (MS) should be totally different from that of SSPD in order to realize meaningful sensitive area and reasonably fast response time for mass-independent detection. Recently, we have succeeded in obtaining mass spectra of Angiotensin I (MW = 1296 Da) at an energy of 17.5 keV using Nb-SSLDs. Since it is known that in NbN SSLDs the response time of SSLDs is governed by kinetic inductance, Nb films with a short London penetration depth have an advantage over NbN. In this study, the relationship between the detector structures and their performance is reported.