Research Institute of Electrical Communication Tohoku University


Keiichi Edamatsu,Professor

Yasuyoshi Mitsumori,Associate Professor

Mark Paul Sadgrove,Associate Professor

Baek Soyoung,Assistant Professor

Fumihiro Kaneda,Assistant Professor

Nobuyuki Matsumoto,Assistant Professor

Naofumi Abe,Research Fellow

(From left)Naofumi Abe, Fumihiro Kaneda, Soyoung Baek
Keiichi Edamatsu, Nobuyuki Matsumoto, Mark Sadgrove, Yasuyoshi Mitsumori


Research Activities

Current information and communication technology utilizes macroscopic and classical physical quantities, such as voltage or frequency of electric fields. The classical technology will reach the limit of information density and speed in the near future. The quantum-mechanical counterpart, “quantum information processing and communication technology”, in which information is carried by microscopic and quantum-mechanical quantities, is expected to overcome the difficulty. Our goal is to develop quantum information devices utilizing quantum interaction between electrons and photons in semiconductor nanostructures, to obtain further understanding of their physics, and to apply them to practical quantum information technologies.

Laboratory Web Page

ECEI Web Page

Quantum-Optical Information Technology(Prof. Edamatsu)

Development of fundamental devices and quantum measurement techniques for quantum info-communication technology (QICT) utilizing photons, novel materials and semiconductor nanostructures.

Research topics

  • Novel techniques for the generation and detection of photon entanglement.
  • QICT devices using optical fibers, waveguides, and semiconductor nanostructures.
  • Techniques for extreme quantum measurement and quantum state synthesis using photons.

Quantum Laser Spectroscopy(Assoc. Prof. Mitsumori)

Development of optical manipulation technique of electrons in semiconductor quantum structures for the realization of QICT

Research topics

  • Coherent optical control of electrons in semi-conductor quantum dots.
  • Quantum optics of semiconductor microcavities.

Quantum Nanophotonics(Assoc. Prof. Sadgrove)

Development of nanophotonic methods for the manipulation of quantum emitters and cold atoms.

Research topics

  • Use of optical nanofibers to produce novel single photon sources.
  • Control of cold atoms using nanophotonic devices.

Fig.1 Schematic picture of unpolarized single-photon generation using a compound defect, a nitrogen vacancy center (NV center), in a diamond. Spheres, designated N and V respectively, indicate a nitrogen atom and a vacancy which comprises an NV center in the diamond lattice. Dynamically and statically unpolarized single-photon emission is induced by laser excitation for a [111]-oriented NV center in (111) diamond.
Fig.2 A gold nanoparticle on the surface of an optical nanofiber is illuminated by a laser, and the scattered light enters the fiber. The output intensity (shown by the spheres at either end of the fiber) depends on the light polarization, and is different for left and right sides of the fiber, that is, it exhibits chirality.x