A 1-MHz low noise preamlifier based on Double Relaxation Oscillation SQUIDs

A.W. Hamster, M.J. van Duuren, G.C.S. Brons, J. Flokstra, H. Rogalla

Research output: Contribution to journalArticleAcademicpeer-review

4 Citations (Scopus)
55 Downloads (Pure)


A low noise and wideband preamplifier based on Double Relaxation Oscillation Superconducting Quantum Interference Devices (DROSs) has been realized. A major advantage of a DROS is that it can be operated in a simple flux modulation. So far, biomagnetic measurements performed in our group required only a limited bandwidth smaller than 100 kHz. Other applications, like for instance readout of radiation and particle detectors, demand a larger bandwidth. In this paper, we will discuss our efforts aimed at increasing the operational bandwidth of a DROS in flux locked loop. Presently, a flux locked loop scheme with a -3 dB bandwidth of 1.45 MHz has been built. With this system a white flux noise of 8 ¿¿0/¿Hz was measured with a 1/f-corner frequency of 10 Hz. The slew rate was 2.5·105 ¿0/s. With the mutual input inductance of 6.7 nH, an input current noise of the preamplifier of 2.5 pA/¿Hz was found and a current slew rate of 80 mA/s. We will discuss the suitability of our DROS-based preamplifier for readout of cryogenic particle detectors based on superconducting tunnel junctions
Original languageEnglish
Pages (from-to)2915-2918
Number of pages4
JournalIEEE transactions on applied superconductivity
Issue number2
Publication statusPublished - 1999


Dive into the research topics of 'A 1-MHz low noise preamlifier based on Double Relaxation Oscillation SQUIDs'. Together they form a unique fingerprint.

Cite this