Our Research
Research on novel functional silicon quantum devices using high-accuracy single-electron control
We aim to achieve high-accuracy control of a single electron using silicon single-electron devices that can transfer a single electron with high accuracy, and to realize new devices that take advantage of its quantum mechanical properties. We are working on observation of ultrafast coherent oscillations of single electrons, control of single-electron wave packets in quantum Hall systems, and collision experiments of single hot electrons.
Si quantum dot single-electron pump for metrology applications
Fast and accurate Si single-electron pumps with a dynamical quantum dot with tunable barriers are promising for the application to quantum current standards and the quantum metrology triangle (QMT) experiments. We have been promoting collaborations with National Metrology Institutes in Europe [Euramet e-SI-Amp] and Japan [JSPS KAKENHI S (Quantum Standards and Ultimate Precision Measurements Based on Single Electrons) ].
Single-electron sensor and data processing
Single electrons are manipulated and monitored using Si nanometer-scale transistors at room temperature. These functions would enable high-sensitivity charge sensor as well as circuits using one electron as one bit of information.
Information thermodynamics
We are studying information thermodynamic concept such as Maxwell’s demon and Landauer’s principle to achieve extreme energy efficient operation of silicon nanodevices.
Silicon valleytronics
We are exploring new functionalities of silicon devices using valley degrees of freedom. At the special silicon interface, valleys that are independent in bulk silicon are strongly coupled and exhibit unusual properties such as direct optical transitions in silicon. Incorporating this property into silicon devices enables gate control of indirect-to-direct optical transitions in silicon.
Nanoscale Silicon-based spin device
Exchange interactions in ferromagnetic semiconductors exhibit various phenomena induced by coupling with charges, photons, and phonons. There are still many unexplored domains in the field of ferromagnetic semiconductor nanodevices. We are particularly interested in reproducing the fundamental physics of magnetic atoms and the underlying physics beyond it(e.g., quantum critical phenomenon) by manipulating the electronic correlation in nanostructures.
