Granular-aluminum superconducting detector for 6 keV X-rays and 2.2 MeV beta sources

X-Ray Induced Secondary Particle Counting With Thin NbTiN Nanowire Superconducting Detector

“…During the past three decades, a range of different materials were implemented. Among them are granular Al [14] and W [15], crystalline NbVN [16], NbN [17], Nb [18], TaN [19], and amorphous WSi [4]. Over the years material and fabrication quality have improved, leading to better and saturated X-ray SNSPDs (X-SNSPD) [19].…”

An ultra-fast superconducting Nb nanowire single-photon detector for soft x-rays

“…Strikingly, the signal amplitude distribution depends significantly on the photon energy spectrum.Already more than a decade before the development of superconducting nanowire single-photon detectors (SNSPD) for the optical and near-infrared wavelength range, serious efforts had been undertaken to adapt this detection principle for X-ray photons with keVenergies. 1,2,3,4 However, these preliminary X-ray detectors struggled with latching, making it difficult to operate them as self-recovering detectors in which superconductivity recovers after photon detection events (called continuous operation mode in this letter). The need to externally reduce the bias current to a value low enough for superconductivity to recover after a detection event results in long dead times and limits the count rates.Very fast and sensitive X-ray single-photon detectors from superconducting nanowires would be very interesting for applications where very high count rates, precise timing, a good signal-to-noise ratio and response in a wide spectral range for photon counting are required.Potential applications comprise experiments with synchrotron X-ray sources, free-electron lasers and hot plasmas (as in nuclear fusion experiments), all emitting bright and pulsed X-ray radiation.…”

“…Already more than a decade before the development of superconducting nanowire single-photon detectors (SNSPD) for the optical and near-infrared wavelength range, serious efforts had been undertaken to adapt this detection principle for X-ray photons with keVenergies. 1,2,3,4 However, these preliminary X-ray detectors struggled with latching, making it difficult to operate them as self-recovering detectors in which superconductivity recovers after photon detection events (called continuous operation mode in this letter). The need to externally reduce the bias current to a value low enough for superconductivity to recover after a detection event results in long dead times and limits the count rates.…”

Soft X-Ray Single-Photon Detection With Superconducting Tantalum Nitride and Niobium Nanowires

“…This is in agreement with the expectations from the hot-spot model: as the hot-spot diameter is smaller than the conduction path width even for 50 keV photons, a bias current above a non-zero threshold [14] must be applied in order to detect photons efficiently. It has been demonstrated that this bias threshold can depend on the energy of detected β-particles [16] and keV ions [15] and also on the operation temperature [16]. At , however, we expect that the energy-dependent bias thresholds are larger than 460 µA (assuming a cylindrical hot-spot [14]), which is already in the latching regime.…”