| Zugriffsnummer | 36764 |
| Dokumenttyp | Zeitschriftenartikel |
| Sprache | Englisch |
| Titel | Investigation of nanoSQUID designs for practical applications |
| Autor(in); Institution |
Bechstein, Sylke; 7.2, Kryophysik und Spektrometrie, PTB-Berlin
Köhn, Claudia; 7.2, Kryophysik und Spektrometrie, PTB-Berlin
Drung, Dietmar; 7.2, Kryophysik und Spektrometrie, PTB-Berlin
Storm, Jan-Hendrik; 7.2, Kryophysik und Spektrometrie, PTB-Berlin
Kieler, Oliver; 2.4, Quantenelektronik, PTB-Braunschweig
Morosh, Viacheslav; 2.4, Quantenelektronik, PTB-Braunschweig
Schurig, Thomas; 7.2, Kryophysik und Spektrometrie, PTB-Berlin
|
| Quelle/Jahr | NanoSQUID Special issue. Superconductor Science and Technology: 30 (2017), 3, 10 S. |
| ISSN | 0953-2048 (PRINT) ; 1361-6668 (ONLINE) |
| DOI | |
| Verlag | Bristol: IOP Publishing |
| Freie Schlagworte | nanoSQUID ; microSQUID ; transformer ; susceptometer ; series SQUID array |
| Zusammenfassung | In the recent past, considerable effort was spent on the development of SQUID designs for magnetic detection in the micro- and nano-scale. Where these novel nanoSQUIDs were mostly of simple format, real applications require more elaborate designs including auxiliary components such as coils and transformers. To this end, we have developed SQUID designs based on conventional Nb/AlOx/Nb Josephson junction (JJ) technology which are intended for material characterization of micro- and nano-sized samples. However, these devices are facing limitations, e.g. regarding operation in applied magnetic fields, which real nanoSQUIDs are expected to overcome. In contrast to superconductor-insulator-superconductor (SIS) junctions which need to be shunted, superconductor-normal conductor-superconductor (SNS) junctions are much more promising for complex nanoSQUID designs. Therefore, a Nb/HfTi/Nb thin-film technology which offers both, nano-patterning and waferscale manufacturing of complex design structures, was used for nanoSQUIDs fabrication. The area of the SNS JJs of these nanoSQUIDs is about 200 nm x 200 nm whereas the typical lateral dimensions of the SIS microSQUID JJs is about 2 μm x 2 μm. In order to enable real practical applications, nanoSQUID designs with a number of implemented auxiliary components and design features, such as gradiometric feedback loops, gradiometric transformers, and rf filters, are carefully investigated. This paper is mainly aiming at summarizing recent achievements and comparing parameters of devices manufactured using our conventional SIS and novel SNS nano-technology. Detailed measurements of the device performance in magnetic fields of up to a few tens of millitesla are presented. This investigation is intended to pave the way for future practical complex nanoSQUID tools. |
