Transfer and detection of a single isolated electron
Electrons in a metal are indistinguishable particles that interact strongly with other electrons and their environment.
Quantum information of a single electron will be immediately lost after the electron is injected into an electrical circuit and mixed up with other electrons. In quantum information processing it is therefore crucial to isolate a single electron from others by confining it into a microscopic container called a quantum dot. For scaling up quantum computers, however, it may be useful to transfer quantum information between distant quantum dots without that information being disturbed in the process.
In this study, Professor Seigo Tarucha and his group at the University of Tokyo’s Graduate School of Engineering developed a technique for transferring a single electron between distant quantum dots through a depleted narrow wire. During the wire transport the electron is completely isolated from other electrons. This transfer is completed fast enough that the quantum information of the electron is not disturbed during the transfer. This technology paves the way to transfer quantum information over longer distances.? It also allows us to perform experiments on quantum scattering and interference for single electrons, a long-held dream of solid-state physicists.
This research was carried out in collaboration with Neel Institute, CNRS and Joseph Fourier University, France and Bochum University, Germany.
Press release (Japanese)
Press release (French)
Sylvain Hermelin, Shintaro Takada, Michihisa Yamamoto, Seigo Tarucha, Andreas D. Wieck, Laurent Saminadayar, Christopher B?uerle and Tristan Meunier,
“Electrons surfing on a sound wave as a platform for quantum optics with flying electrons,”
Nature 477 (2011): 435-438 doi: 10.1038/nature10416.