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Repeated temperature modulation epitaxy for p-type doping and light-emitting diode based on ZnO
Since the successful demonstration of a blue light-emitting diode (LED)1, potential materials for making short-wavelength LEDs and diode lasers have been attracting increasing interest as the demandsExpand
High‐Density Carrier Accumulation in ZnO Field‐Effect Transistors Gated by Electric Double Layers of Ionic Liquids
Very recently, electric-field-induced superconductivity in an insulator was realized by tuning charge carrier to a high density level (1 × 1014 cm−2). To increase the maximum attainable carrierExpand
Trajectory of the anomalous Hall effect towards the quantized state in a ferromagnetic topological insulator
Quantized resistivity values for 2D electron systems don’t necessarily result from an external magnetic field as in the ‘normal’ quantum Hall effect; they can arise due to a material's intrinsicExpand
Quantum Hall Effect in Polar Oxide Heterostructures
Demonstration of the quantum Hall effect in an oxide heterostructure presents the possibility of combining quantum Hall physics with the versatile functionality of metal oxides in complex heterostructures. Expand
Magnetic topological insulators
The importance of global band topology is unequivocally recognized in condensed matter physics, and new states of matter, such as topological insulators, have been discovered. Owing to their bulkExpand
Observation of the fractional quantum Hall effect in an oxide.
The present study represents a technological advance in oxide electronics that provides opportunities to explore strongly correlated phenomena in quantum transport of dilute carriers in MgZnO/ ZnO heterostructures grown by molecular-beam epitaxy. Expand
Fermi-level-dependent charge-to-spin current conversion by Dirac surface states of topological insulators
The spin–momentum locking of Dirac surface states offers intriguing possibilities for converting between charge and spin currents. Experiments show that fine tuning of the Fermi level is critical forExpand
Nitrogen doped MgxZn1−xO/ZnO single heterostructure ultraviolet light-emitting diodes on ZnO substrates
We have grown nitrogen-doped MgxZn1−xO:N films on Zn-polar ZnO single crystal substrates by molecular beam epitaxy. As N-sources, we employed NO-plasma or NH3 gas itself. As x increased, optimumExpand
High Electron Mobility Exceeding 104 cm2 V-1 s-1 in MgxZn1-xO/ZnO Single Heterostructures Grown by Molecular Beam Epitaxy
Nominally undoped MgxZn1-xO/ZnO (x = 0.05 and 0.08) single heterostructures were prepared on Zn-polar ZnO substrates by using plasma assisted molecular beam epitaxy (MBE). The samples showed aExpand
Electrostatic and electrochemical nature of liquid-gated electric-double-layer transistors based on oxide semiconductors.
The temperature-frequency mapping of EIS was demonstrated as a "phase diagram" to distinguish the electrostatic or electrochemical nature of such highly charged EDL interfaces with densities of up to 8 × 10(14) cm(-2), providing a guideline for electric-field-induced electronic phenomena and a simple method for distinguishing electrostatic and electrochemical charging in EDLTs. Expand