Time-of-Flight Mass Spectrometry With Latching Nb Meander Detectors

Mass Spectrometry is widely used for protein characterization, structural virology, drug discovery, and clinical chemistry. However, the detection efficiency of existing detectors for mass spectrometry degrades rapidly as mass is increased, and is only ~ 10^-5 at 10⁶ Da. Superconducting detectors provide detection efficiency that is essentially independent of mass, and previous efforts have explored the use of superconducting tunnel junctions (STJs) and normal-insulator-superconductor (NIS) microcalorimeters as detectors. Both STJ and NIS detectors, however have active areas limited to ~ 1 mm², well below the ~ 1 cm² required for a viable system. Microwave-interrogated microstripline meander detectors have the potential to provide the necessary area and speed. We describe such a design and present initial spectra of representative ionized biological molecules obtained from simple prototype detectors mounted on a cryocooler and interfaced to a commercial mass spectrometer.