{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T18:57:38Z","timestamp":1772823458752,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,12,30]],"date-time":"2019-12-30T00:00:00Z","timestamp":1577664000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Scanning Superconducting Quantum Interference Device (SQUID) Susceptometry simultaneously images the local magnetic fields and susceptibilities above a sample with sub-micron spatial resolution. Further development of this technique requires a thorough understanding of the current, voltage, and flux (    I V \u03a6    ) characteristics of scanning SQUID susceptometers. These sensors often have striking anomalies in their current\u2013voltage characteristics, which we believe to be due to electromagnetic resonances. The effect of these resonances on the performance of these SQUIDs is unknown. To explore the origin and impact of the resonances, we develop a model that qualitatively reproduces the experimentally-determined     I V \u03a6     characteristics of our scanning SQUID susceptometers. We use this model to calculate the noise characteristics of SQUIDs of different designs. We find that the calculated ultimate flux noise is better in susceptometers with damping resistors that diminish the resonances than in susceptometers without damping resistors. Such calculations will enable the optimization of the signal-to-noise characteristics of scanning SQUID susceptometers.<\/jats:p>","DOI":"10.3390\/s20010204","type":"journal-article","created":{"date-parts":[[2020,1,3]],"date-time":"2020-01-03T03:28:53Z","timestamp":1578022133000},"page":"204","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Influence of Resonances on the Noise Performance of SQUID Susceptometers"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9994-8165","authenticated-orcid":false,"given":"Samantha I.","family":"Davis","sequence":"first","affiliation":[{"name":"Department of Physics, Stanford University, Stanford, CA 94305-4045, USA"},{"name":"California Institute of Technology\u2014The Division of Physics, Mathematics and Astronomy, 1200 E California Blvd, Pasadena, CA 91125, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John R.","family":"Kirtley","sequence":"additional","affiliation":[{"name":"Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kathryn A.","family":"Moler","sequence":"additional","affiliation":[{"name":"Department of Physics, Stanford University, Stanford, CA 94305-4045, USA"},{"name":"Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USA"},{"name":"Department of Applied Physics, Stanford University, Stanford, CA 94305, USA"},{"name":"Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Clarke, J., and Braginski, A.I. (2004). The SQUID Handbook, Wiley Online Library.","DOI":"10.1002\/3527603646"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2597","DOI":"10.1063\/1.1408276","article-title":"Dc superconducting quantum interference device amplifier for gravitational wave detectors with a true noise temperature of 16 \u03bcK","volume":"79","author":"Vinante","year":"2001","journal-title":"Appl. Phys. Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1446","DOI":"10.1063\/1.126059","article-title":"Two-stage superconducting-quantum-interference-device amplifier in a high-Q gravitational wave transducer","volume":"76","author":"Harry","year":"2000","journal-title":"Appl. Phys. Lett."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1016\/j.neuroimage.2011.11.074","article-title":"Magnetoencephalography: From SQUIDs to neuroscience: Neuroimage 20th anniversary special edition","volume":"61","author":"Hari","year":"2012","journal-title":"Neuroimage"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Devoret, M.H., Wallraff, A., and Martinis, J.M. (2004). Superconducting qubits: A short review. arXiv.","DOI":"10.1016\/S0924-8099(03)80036-7"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1146\/annurev.matsci.29.1.117","article-title":"Scanning SQUID microscopy","volume":"29","author":"Kirtley","year":"1999","journal-title":"Annu. Rev. Mater. Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2128","DOI":"10.1063\/1.109448","article-title":"Magnetic microscopy using a liquid nitrogen cooled YBa2Cu3O7 superconducting quantum interference device","volume":"62","author":"Black","year":"1993","journal-title":"Appl. Phys. Lett."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"3825","DOI":"10.1063\/1.1515384","article-title":"Scanning \u03bc-superconduction quantum interference device force microscope","volume":"73","author":"Veauvy","year":"2002","journal-title":"Rev. Sci. Instrum."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1046","DOI":"10.1021\/nl100009r","article-title":"Self-aligned nanoscale SQUID on a tip","volume":"10","author":"Finkler","year":"2010","journal-title":"Nano Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1693","DOI":"10.1063\/1.110687","article-title":"Imaging of magnetic vortices in superconducting networks and clusters by scanning SQUID microscopy","volume":"63","author":"Vu","year":"1993","journal-title":"Appl. Phys. Lett."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1138","DOI":"10.1063\/1.113838","article-title":"High-resolution scanning SQUID microscope","volume":"66","author":"Kirtley","year":"1995","journal-title":"Appl. Phys. Lett."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2361","DOI":"10.1063\/1.1364668","article-title":"Scanning superconducting quantum interference device susceptometry","volume":"72","author":"Gardner","year":"2001","journal-title":"Rev. Sci. Instrum."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"126501","DOI":"10.1088\/0034-4885\/73\/12\/126501","article-title":"Fundamental studies of superconductors using scanning magnetic imaging","volume":"73","author":"Kirtley","year":"2010","journal-title":"Rep. Prog. Phys."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"053704","DOI":"10.1063\/1.2932341","article-title":"Gradiometric micro-SQUID susceptometer for scanning measurements of mesoscopic samples","volume":"79","author":"Huber","year":"2008","journal-title":"Rev. Sci. Instrum."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"093702","DOI":"10.1063\/1.4961982","article-title":"Scanning SQUID susceptometers with sub-micron spatial resolution","volume":"87","author":"Kirtley","year":"2016","journal-title":"Rev. Sci. Instrum."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1007\/BF00655097","article-title":"dc SQUID: Noise and Optimization","volume":"29","author":"Tesche","year":"1977","journal-title":"J. Low Temp. Phys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"383","DOI":"10.1007\/BF00655060","article-title":"Comment on: \u201cDc SQUID: Noise and optimization\u201d by Tesche and Clarke","volume":"46","author":"Bruines","year":"1982","journal-title":"J. Low Temp. Phys."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1007\/BF00681634","article-title":"Measurements of the dynamic input impedance of a dc SQUID","volume":"61","author":"Hilbert","year":"1985","journal-title":"J. Low Temp. Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1000","DOI":"10.1063\/1.351824","article-title":"Modeling the dc superconducting quantum interference device coupled to the multiturn input coil. III","volume":"72","author":"Enpuku","year":"1992","journal-title":"J. Appl. Phys."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4048","DOI":"10.1109\/77.947383","article-title":"DC SQUID series array amplifiers with 120 MHz bandwidth (corrected)","volume":"11","author":"Huber","year":"2001","journal-title":"IEEE Trans. Appl. Supercond."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1007\/BF00683902","article-title":"Effects on dc SQUID characteristics of damping of input coil resonances","volume":"68","author":"Knuutila","year":"1987","journal-title":"J. Low Temp. Phys."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1016\/0031-9163(62)91369-0","article-title":"Possible new effects in superconductive tunnelling","volume":"1","author":"Josephson","year":"1962","journal-title":"Phys. Lett."},{"key":"ref_23","unstructured":"(2019, September 13). IC Design Software for Linux, OS X and Windows. Available online: http:\/\/www.wrcad.com\/."},{"key":"ref_24","unstructured":"(2019, March 11). JSPICE. Available online: https:\/\/ptolemy.berkeley.edu\/projects\/embedded\/pubs\/downloads\/spice\/jspice.html."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/1\/204\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:46:46Z","timestamp":1760190406000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/1\/204"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,12,30]]},"references-count":24,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2020,1]]}},"alternative-id":["s20010204"],"URL":"https:\/\/doi.org\/10.3390\/s20010204","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,12,30]]}}}