| Zugriffsnummer | 32605 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Englisch |
| Titel | Advanced SQUID read-out electronics |
| Autor(in); Institution |
Drung, Dietmar; 9.33, Kryoelektronik, PTB-Berlin
|
| Quelle/Jahr | Squid sensors : fundamentals, fabrication and applications: [proceedings of the NATO Advanced Study Institute on SQUID Sensors: Fundamentals, Fabrication and Applications, Acquafredda di Maratea, Italy, June 18-30, 1995]:(1996), 63 - 116 |
| ISBN | 0-7923-4350-6 (print) ; 978-94-011-5674-5 (online) |
| DOI | |
| Verlag | Kluwer Academic: Dordrecht [u.a.] |
| Konferenzangaben | NATO Advanced Study Institute on SQUID Sensors: Fundamentals, Fabrication and Applications, Maratea, June 18-30, 1995, Italy |
| Freie Schlagworte | Measurement Science and Instrumentation ; Neuroradiology ; Cardiology ; Characterization and Evaluation of Materials ; Geophysics/Geodesy |
| Zusammenfassung | Superconducting quantum interference devices (SQUIDs) are the most sensitive devices for measuring weak magnetic fields. Beside the SQUID itself, the design of the read-out electronics decisively determines the performance of the whole sensor. In standard read-out electronics, a cooled impedance-matching transformer between SQUID and preamplifier, and a flux modulation technique are employed. Recently, several novel SQUID read-out concepts without flux modulation have been developed, mainly for biomagnetic multichannel systems. This chapter gives a description and comparison of the most important ones: concepts using multiple SQUIDs, SQUIDs with additional positive feedback, relaxation oscillation SQUIDs, and digital SQUIDs. Both the noise and the dynamic behavior are discussed, and a simple model for the achievable speed of a directly-coupled feedback loop without flux modulation is presented, which allows one to estimate the dynamic merits of the various SQUID concepts. |
