Josephson junction

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July 23, 2026

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A Josephson junction is an electronic device consisting of two superconducting layers separated by a thin insulating layer. When a low current flows between the superconductors, electron pairs can tunnel through the insulator. This phenomenon, known as the Josephson effect, was predicted by physicist Brian D. Josephson in 1962.123

If a battery is connected, the current oscillates, and no net current flows. However, magnetic fields can influence this effect, making Josephson junctions useful for measuring very weak magnetic fields. They are also used in devices like the superconducting quantum interference device (SQUID) and as precise standards for voltage measurement.12

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conductive ceramics
Superconductors
…as advanced devices such as Josephson junctions and so-called SQUIDs (superconducting quantum interference devices). Josephson junctions, formed at contacts between two superconductors, can convert a direct voltage into an alternating current whose frequency rises with applied voltage. Frequencies in the superhigh frequency (SHF) range can be achieved. SQUIDs are highly…
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…as advanced devices such as Josephson junctions and so-called SQUIDs (superconducting quantum interference devices). Josephson junctions, formed at contacts between two superconductors, can convert a direct voltage into an alternating current whose frequency rises with applied voltage. Frequencies in the superhigh frequency (SHF) range can be achieved. SQUIDs are highly…
Read More

electronics
Superconducting electronics
…insulating film between them (the Josephson junction) and the effects of small magnetic fields on this current.
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…insulating film between them (the Josephson junction) and the effects of small magnetic fields on this current.
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Brian D. Josephson
…to be known as a Josephson junction. Josephson extended earlier work in tunneling, the phenomenon by which electrons functioning as radiated waves can penetrate solids, done by Esaki and Giaever. He showed theoretically that tunneling between two superconductors could have very special characteristics—e.g., flow across an insulating layer without the…
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…to be known as a Josephson junction. Josephson extended earlier work in tunneling, the phenomenon by which electrons functioning as radiated waves can penetrate solids, done by Esaki and Giaever. He showed theoretically that tunneling between two superconductors could have very special characteristics—e.g., flow across an insulating layer without the…
Read More