| Zugriffsnummer | 22975 |
| Dokumenttyp | Konferenzartikel in Zeitschrift |
| Sprache | Englisch |
| Titel | A single-stage SQUID multiplexer for TES array readout |
| Autor(in); Institution |
Beyer, Jörn; 7.5, Kryo- und Vakuumphysik, PTB-Berlin
Drung, Dietmar; 7.5, Kryo- und Vakuumphysik, PTB-Berlin
Peters, Margret; 7.5, Kryo- und Vakuumphysik, PTB-Berlin
Schurig, Thomas; 7.5, Kryo- und Vakuumphysik, PTB-Berlin
Bandler, Simon; NASA/Goddard Space Flight Center, Greenbelt, USA
|
| Quelle/Jahr | IEEE Transactions on Applied Superconductivity: 19 (2009), 3,1, 505 - 508 |
| ISSN | 1051-8223 |
| DOI | |
| Verlag | New York, NY: Inst. |
| Konferenzangaben | Applied Superconductivity Conference 2008, Chicago, August 17 - 22, 2008, USA |
| Zusammenfassung | SQUIDs are detectors of changes in magnetic flux and are used in precision measurement systems to sense changes in various physical quantities, e.g. magnetic field, electric current or mechanical displacement, which can be transformed into changes in the magnetic flux threading the SQUID loop. A SQUID based sensor able to detect a dc signal can be formed by a series array of individual SQUIDs with different sensitivities to the signal of interest, for instance a series array of SQUID magnetometers with different sensitive areas [1]. Based on this concept we have developed practical and highly sensitive sensors for dc current based on SQUID series arrays. In these devices, the SQUID loops of all array elements are identical. However, the input signal current is coupled tightly but non-uniformly to the individual array elements. This leads to a single-valued overall voltage-vs.-current response and, therefore, allows a dc input signal to be measured. The response would be compromised by random as well as by equal flux offsets in the individual array elements, which can occur during cooldown or operation. Our design ensures that such flux offsets are avoided or can be compensated for by the readout electronics. We have realized sensors with 18 and 36 array elements. The expected single-valued overall voltage response and white noise levels down to 7.5 pA/rtHz at 4.2 K are achieved. We present the realized sensor design and simulations of the device characteristics. Locked mode operation and noise performance of our novel dc current sensors are discussed. [1] P.Carelli et.al., Europhys.Lett. 39, 569 (1997) |
