VTT quantum-Hall setup

Author

Varpula, T. ; Seppa, H.

Author_Institution

Metrol. Res. Inst., Espoo, Finland

fYear

1990

fDate

11-14 June 1990

Firstpage

352

Lastpage

353

Abstract

The authors present a compact setup for quantum Hall measurements consisting of an overlapped-tube cryogenic current comparator, where the imbalance is detected with a sensitive DC-SQUID (superconducting quantum interference device) magnetometer, and a small superconducting magnet system operated in a standard liquid-helium storage dewar. The system also incorporates PC-controlled electronics, which facilitates automatic measurements. The setup has been developed for a small-scale national standards laboratory where resistance calibrations at an uncertainty level of 10/sup -8/ are performed. A block diagram of the electronics of the measurement setup is shown along with a 1.5 K insert that includes a complete superconducting magnet system and the quantum-Hall probe.<>

Keywords

SQUIDs; calibration; computerised instrumentation; electric resistance measurement; magnetometers; measurement standards; microcomputer applications; quantum Hall effect; superconducting magnets; 1.5 K; DC-SQUID; PC-controlled electronics; VTT; automatic measurements; magnetometer; national standards laboratory; overlapped-tube cryogenic current comparator; quantum Hall measurements; quantum-Hall probe; resistance calibrations; superconducting magnet; superconducting quantum interference device; Cryogenics; Current measurement; Electrical resistance measurement; Interference; Laboratories; Measurement standards; SQUID magnetometers; Standards development; Superconducting devices; Superconducting magnets;

fLanguage

English

Publisher

ieee

Conference_Titel

Precision Electromagnetic Measurements, 1990. CPEM '90 Digest., Conference on

Conference_Location

Ottawa, Ontario, Canada

Type

conf

DOI

10.1109/CPEM.1990.110056

Filename

110056