Title: Thermal fluctuation noise in Mo/Au superconducting transition-edge sensor microcalorimeters

Abstract

In many superconducting transition-edge sensor (TES) microcalorimeters, the measured electrical noise exceeds theoretical estimates based on a thermal model of a single body thermally connected to a heat bath. In this work, we report on noise and complex impedance measurements of a range of designs of TESs made with a Mo/Au bilayer. We have fitted the measured data using a two-body model, where the x-ray absorber and the TES are connected by an internal thermal conductance G_ae. We find that the so-called excess noise measured in these devices is consistent with the noise generated from the internal thermal fluctuations between the x-ray absorber and the TES. Our fitted parameters are consistent with the origin of G_ae being from the finite thermal conductance of the TES itself. These results suggest that even in these relatively low resistance Mo/Au TESs, the internal thermal conductance of the TES may add significant additional noise and could account for all the measured excess noise. Furthermore, we find that around regions of the superconducting transition with rapidly changing derivative of resistance with respect to temperature, an additional noise mechanism may dominate. These observations may lead to a greater understanding of TES devices and allow the designmore » of TES microcalorimeters with improved performance.« less

Authors:

Wakeham, N. A.  ^[1];

• Search DOE PAGES for author "Wakeham, N. A."
• Search DOE PAGES for ORCID "0000-0001-8397-9338"

Adams, J. S. ^[1]; Bandler, S. R.  ^[2];

• Search DOE PAGES for author "Bandler, S. R."
• Search DOE PAGES for ORCID "0000-0002-5112-8106"

Beaumont, S. ^[1]; Chervenak, J. A. ^[2]; Datesman, A. M. ^[3]; Eckart, M. E. ^[4]; Finkbeiner, F. M. ^[5]; Hummatov, R.  ^[1];

• Search DOE PAGES for author "Hummatov, R."
• Search DOE PAGES for ORCID "0000-0002-3556-0636"

Kelley, R. L. ^[2]; Kilbourne, C. A.  ^[2];

• Search DOE PAGES for author "Kilbourne, C. A."
• Search DOE PAGES for ORCID "0000-0001-9464-4103"

Miniussi, A. R.  ^[1];

• Search DOE PAGES for author "Miniussi, A. R."
• Search DOE PAGES for ORCID "0000-0003-0622-5174"

Porter, F. S. ^[2]; Sadleir, J. E. ^[2]; Sakai, K.  ^[1];

• Search DOE PAGES for author "Sakai, K."
• Search DOE PAGES for ORCID "0000-0002-9247-3010"

Smith, S. J. ^[1]; Wassell, E. J. ^[3]

---

+ Show Author Affiliations

1. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Univ. of Maryland Baltimore County (UMBC), Baltimore, MD (United States)
2. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
3. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); KBRwyle, Lexington Park, MD (United States)
4. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
5. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Sigma Space Corp., Lanham, MD (United States)

Publication Date:

Tue Apr 23 00:00:00 EDT 2019

Research Org.:

Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:

1527293

Alternate Identifier(s):

OSTI ID: 1508437

Report Number(s):

LLNL-JRNL-764481
Journal ID: ISSN 0021-8979; 954491

Grant/Contract Number:  

AC52-07NA27344

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Applied Physics

Additional Journal Information:

Journal Volume: 125; Journal Issue: 16; Journal ID: ISSN 0021-8979

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 79 ASTRONOMY AND ASTROPHYSICS