Browse Definitions:
Definition

Josephson junction

A Josephson junction is a type of electronic circuit capable of switching at very high speeds when operated at temperatures approaching absolute zero. Named for the British physicist who designed it, a Josephson junction exploits the phenomenon of superconductivity, the ability of certain materials to conduct electric current with practically zero resistance. Josephson junctions are used in certain specialized instruments such as highly-sensitive microwave detectors, magnetometers, and QUIDs.

A Josephson junction is made up of two superconductors, separated by a nonsuperconducting layer so thin that electrons can cross through the insulating barrier. The flow of current between the superconductors in the absence of an applied voltage is called a Josephson current, and the movement of electrons across the barrier is known as Josephson tunneling. Two or more junctions joined by superconducting paths form what is called a Josephson interferometer.

While researching superconductivity, Brian David Josephson studied the properties of a junction between two superconductors. Following up on earlier work by Leo Esaki and Ivar Giaever, he demonstrated that in a situation when there is electron flow between two superconductors through an insulating layer (in the absence of an applied voltage), and a voltage is applied, the current stops flowing and oscillates at a high frequency.

The Josephson effect is influenced by magnetic fields in the vicinity, a capacity that enables the Josephson junction to be used in devices that measure extremely weak magnetic fields, such as superconducting quantum interference devices (SQUIDs). For their efforts, Josephson, Esaki, and Giaever shared the Nobel Prize for Physics in 1973.

This was last updated in September 2005

Continue Reading About Josephson junction

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

  • risk map (risk heat map)

    A risk map, also known as a risk heat map, is a data visualization tool for communicating specific risks an organization faces. A...

  • internal audit (IA)

    An internal audit (IA) is an organizational initiative to monitor and analyze its own business operations in order to determine ...

  • pure risk (absolute risk)

    Pure risk, also called absolute risk, is a category of threat that is beyond human control and has only one possible outcome if ...

SearchCloudProvider

  • cloud ecosystem

    A cloud ecosystem is a complex system of interdependent components that all work together to enable cloud services.

  • cloud services

    Cloud services is an umbrella term that may refer to a variety of resources provided over the internet, or to professional ...

  • uncloud (de-cloud)

    The term uncloud describes the action or process of removing applications and data from a cloud computing platform.

SearchSecurity

  • cyberextortion

    Cyberextortion is a crime involving an attack or threat of an attack coupled with a demand for money or some other response in ...

  • Cybercrime

    Cybercrime is any criminal activity that involves a computer, networked device or a network.

  • National Security Agency (NSA)

    The National Security Agency is the official U.S. cryptologic organization of the United States Intelligence Community under the ...

SearchHealthIT

  • Practice Fusion

    Practice Fusion Inc. is a San Francisco-based company that developed a free electronic health record (EHR) system available to ...

  • RHIA (Registered Health Information Administrator)

    An RHIA, or registered health information administrator, is a certified professional who oversees the creation and use of patient...

  • 21st Century Cures Act

    The 21st Century Cures Act is a wide-ranging healthcare bill that funds medical research and development, medical device ...

SearchDisasterRecovery

SearchStorage

  • Random Access Memory (RAM)

    Random Access Memory (RAM) is the hardware in a computing device where the operating system (OS), application programs and data ...

  • floating gate transistor (FGT)

    A floating gate transistor (FGT) is a complementary metal-oxide semiconductor (CMOS) technology capable of holding an electrical ...

  • bad block

    A bad block is an area of storage media that is no longer reliable for storing and retrieving data because it has been physically...

SearchSolidStateStorage

  • hybrid hard disk drive (HDD)

    A hybrid hard disk drive is an electromechanical spinning hard disk that contains some amount of NAND Flash memory.

Close