Influence of Resonances on the Noise Performance of SQUID Susceptometers
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...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-12-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/20/1/204 |
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| author | Samantha I. Davis John R. Kirtley Kathryn A. Moler |
| author_facet | Samantha I. Davis John R. Kirtley Kathryn A. Moler |
| author_sort | Samantha I. Davis |
| collection | DOAJ |
| description | 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 (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mi>V</mi> <mo>Φ</mo> </mrow> </semantics> </math> </inline-formula>) characteristics of scanning SQUID susceptometers. These sensors often have striking anomalies in their current−voltage 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 <inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mi>V</mi> <mo>Φ</mo> </mrow> </semantics> </math> </inline-formula> 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. |
| first_indexed | 2024-04-11T12:53:03Z |
| format | Article |
| id | doaj.art-a03b5f4113364cb59b0af9151563a1dd |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T12:53:03Z |
| publishDate | 2019-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-a03b5f4113364cb59b0af9151563a1dd2022-12-22T04:23:09ZengMDPI AGSensors1424-82202019-12-0120120410.3390/s20010204s20010204Influence of Resonances on the Noise Performance of SQUID SusceptometersSamantha I. Davis0John R. Kirtley1Kathryn A. Moler2Department of Physics, Stanford University, Stanford, CA 94305-4045, USAGeballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USADepartment of Physics, Stanford University, Stanford, CA 94305-4045, USAScanning 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 (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mi>V</mi> <mo>Φ</mo> </mrow> </semantics> </math> </inline-formula>) characteristics of scanning SQUID susceptometers. These sensors often have striking anomalies in their current−voltage 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 <inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mi>V</mi> <mo>Φ</mo> </mrow> </semantics> </math> </inline-formula> 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.https://www.mdpi.com/1424-8220/20/1/204squidsusceptometersnoisescanning |
| spellingShingle | Samantha I. Davis John R. Kirtley Kathryn A. Moler Influence of Resonances on the Noise Performance of SQUID Susceptometers Sensors squid susceptometers noise scanning |
| title | Influence of Resonances on the Noise Performance of SQUID Susceptometers |
| title_full | Influence of Resonances on the Noise Performance of SQUID Susceptometers |
| title_fullStr | Influence of Resonances on the Noise Performance of SQUID Susceptometers |
| title_full_unstemmed | Influence of Resonances on the Noise Performance of SQUID Susceptometers |
| title_short | Influence of Resonances on the Noise Performance of SQUID Susceptometers |
| title_sort | influence of resonances on the noise performance of squid susceptometers |
| topic | squid susceptometers noise scanning |
| url | https://www.mdpi.com/1424-8220/20/1/204 |
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