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A Directly Coupled Superconducting Quantum Interference Device Magnetometer Fabricated in Magnesium Diboride by Focused Ion Beam

G. Burnell·D. -J. Kang·D. A. Ansell·H. -N. Lee·S. -H. Moon·E. J. Tarte·M. G. Blamire
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Abstract

We report the fabrication of a directly coupled superconducting quantum interference device (SQUID) magnetometer in MgB2 using a focused ion beam (FIB) to create Josephson junctions in a 70 nm thick film of MgB2. The SQUID shows a voltage modulation (deltaV) of 175 mV at a temperature of 10 K and operates over a temperature range from 10 K to 24 K. We find excellent agreement between the measured maximum transfer functions and those predicted by theory. We have measured the magnetic flux noise at 20 K to be as low as 14 micro Phi-0 per root Hz.

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G. Burnell, D. -J. Kang, D. A. Ansell, H. -N. Lee, S. -H. Moon, E. J. Tarte, M. G. Blamire. 2002-03-26. A Directly Coupled Superconducting Quantum Interference Device Magnetometer Fabricated in Magnesium Diboride by Focused Ion Beam. https://doi.org/10.1063/1.1491599

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