Quantum-Optical Information Technology

Group Web Site

[ Professor ] Keiichi Edamatsu
Quantum-Optical Information Technology

[ Associate Professor ] Yasuyoshi Mitsumori
Quantum Laser Spectroscopy

[ Assistant Professor* ] Nobuyuki Matsumoto

[ Assistant Professor* ] Fumihiro Kaneda

[ Assistant Professor ] Soyoung Baek

[ Research Fellow ] Bin Ho Le

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

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
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.

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 semiconductor quantum dots.
  • Quantum optics of semiconductor microcavities.
Fig.2 An illustration of the scheme for producing frequency-entangled photons. A nonlinear crystal has two different poling periods so that produced photon pairs with orthogonally polarized photon pairs can be frequency entangled.