National Physical Laboratory

Single-electron-pump THz applications

Project dates: 1 Jul 2011 – 31 Dec 2011

The aim of this project was to investigate the interactions between THz photons and single electrons in electron pumps.

There were two proposed experiments:

  1. Detection of THz photon emission from excited electrons in an electron pump using an RHUL THz detector.
  2. Detection of THz photons from an external source by exciting electrons in an electron pump.

These experiments would show whether single-electron pumps could be used as single-THz-photon sources or detectors in THz-wave applications. The ideas here are based on the existing single-electron-pump technologies developed by NPL and THz detection technologies developed by RHUL. The proposed detectors potentially have improved performance over existing detectors (e.g. higher operation temperatures, ability to tune energy-sensitivity, etc). In addition, these experiments would provide vital information on the underlying mechanisms of single-electron pumps currently being studied at NPL and elsewhere towards the quantum current standard application.

Through this project, we have developed a capability to perform measurements of integrated THz optics/semiconductor quantum transport devices. In particular, we have fabricated and tested a prototype THz detector based on single-electron-pump devices. What is unique to this device is that there is scope to tune the energy sensitivity (excitation gap energy) by an external magnetic field. For this we would require installation of THz optics (waveguides) in cryogenic systems with superconducting magnets at NPL or RHUL. Such capabilities would put us (RHUL and NPL) into a strong leading status in the fields of THz optics applications and single-electron-device applications.

NPL staff involved with the project

Masaya Kataoka
Patrick See


  • Royal Holloway, University of London (Spas Spasov, Vladimir Antonov, Katie Porsch, Stephen Pelling)
Last Updated: 28 Feb 2012
Created: 27 Feb 2012


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