Use of Transition Models to Design High Performance TESs for the LCLS-II Soft X-Ray Spectrometer

Journal Article · Mon Mar 04 00:00:00 EST 2019 · IEEE Transactions on Applied Superconductivity

DOI:https://doi.org/10.1109/tasc.2019.2903032· OSTI ID:1528855

Morgan, Kelsey M.  ^[1]; Becker, Dan T.  ^[1]; Bennett, Douglas Alan ^[2]; Doriese, William B. ^[2]; Gard, Johnathon D. ^[1]; Irwin, Kent D. ^[3]; Lee, Sang Jun  ^[4]; Li, Dale ^[4]; Mates, John A. B. ^[1]; Pappas, Christine G. ^[1]; Schmidt, Dan R. ^[2]; Titus, Charles J.  ^[3]; Van Winkle, Dan D. ^[4]; Ullom, Joel N. ^[1]; Wessels, Abigail ^[1]; Swetz, Daniel S. ^[2]

---

1. Univ. of Colorado, Boulder, CO (United States)
2. National Inst. of Standards and Technology (NIST), Boulder, CO (United States)
3. Stanford Univ., CA (United States)
4. SLAC National Accelerator Lab., Menlo Park, CA (United States)

We are designing an array of transition-edge sensor (TES) microcalorimeters for a soft X-ray spectrometer at the Linac Coherent Light Source at SLAC National Accelerator Laboratory to coincide with upgrades to the free electron laser facility. The complete spectrometer will have 1000 TES pixels with energy resolution of 0.5 eV full-width at half-maximum (FWHM) for incident energies below 1 keV while maintaining pulse decay-time constants shorter than 100 μs. In the past, TES pixels have often been designed for a particular scientific application via a combination of simple scaling relations and trial-and-error experimentation with device geometry. We have improved upon this process by using our understanding of transition physics to guide TES design. Using the two-fluid approximation of the phase-slip line model for TES resistance, we observe how the geometry and critical temperature of a TES will affect the shape of the transition. We have used these techniques to design sensors with a critical temperature of 55 mK. The best sensors achieve an energy resolution of 0.75 eV FWHM at 1.25 keV. Building upon this result, we show how the next generation of sensors can be designed to reach our goal of 0.5 eV resolution.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-76SF00515
• OSTI ID: 1528855
• Journal Information: IEEE Transactions on Applied Superconductivity, Vol. 29, Issue 5; ISSN 1051-8223
• Publisher: Institute of Electrical and Electronics Engineers (IEEE)
• Country of Publication: United States
• Language: English

Related Subjects

47 OTHER INSTRUMENTATION
Superconducting thin films
thin film sensors
x-ray detectors