19 citations · 82 across the 10 of their papers we have counts for
8 papers · 1 filter
Introduction of deep level impurities, S, Se, and Zn, into Si wafers for high-temperature operation of a Si qubit
Yoshisuke Ban, Kimihiko Kato, Shota Iizuka +5
To realize high-temperature operation of Si qubits, deep impurity levels with large confinement energy, which are hardly thermally excited, have been introduced into Si wafers. Gro…
Impurity band conduction in group-IV ferromagnetic semiconductor Ge1-xFex with nanoscale fluctuations in Fe concentration
Yoshisuke Ban, Yuki K. Wakabayashi, Ryosho Nakane +1
We study the carrier transport and magnetic properties of group-IV-based ferromagnetic semiconductor Ge1-xFex thin films (Fe concentration x = 2.3 - 14 %) with and without boron (B…
Tunneling magnetoresistance in trilayer structures composed of group-IV ferromagnetic semiconductor Ge1-xFex, MgO, and Fe
Yuki K. Wakabayashi, Kohei Okamoto, Yoshisuke Ban +3
Group-IV-based ferromagnetic semiconductor Ge1-xFex (GeFe) is one of the most promising materials for efficient spin injectors and detectors for Si and Ge. Recent first principles…
Origin of the large positive magnetoresistance in Ge1-xMnx granular thin films
Yuki K. Wakabayashi, Ryota Akiyama, Yukiharu Takeda +9
GeMn granular thin films are a unique and promising material for spintronics applications due to large positive magnetoresistance (MR). Previous studies on GeMn have suggested that…
Electronic Structure of the Ferromagnetic Semiconductor Fe-doped Ge Revealed by Soft X-ray Angle-Resolved Photoemission Spectroscopy
Shoya Sakamoto, Yuki K. Wakabayashi, Yukiharu Takeda +7
GeFe (Ge:Fe) shows ferromagnetic behavior up to a relatively high temperature of 210 K, and hence is a promising material for spintronic applications compatible with…
Properties of group-IV-based ferromagnetic semiconductor GeFe: Growth temperature dependence, lattice constant, location of Fe atoms, and their relevance to the magnetic properties
Yuki Wakabayashi, Shinobu Ohya, Yoshisuke Ban +1
We report the growth temperature dependence of the properties of the group-IV-based ferromagnetic semiconductor Ge1-xFex films (x = 6.5% and 10.5%), including the lattice constant,…
Carrier transport properties of the Group-IV ferromagnetic semiconductor Ge1-xFex with and without boron doping
Yoshisuke Ban, Yuki Wakabayashi, Ryota Akiyama +2
We have investigated the transport and magnetic properties of group-IV ferromagnetic semiconductor Ge1-xFex films (x = 1.0 and 2.3 %) with and without boron doping grown by molecul…
Annealing-induced enhancement of ferromagnetism and nano-particle formation in ferromagnetic-semiconductor GeFe
Yuki Wakabayashi, Yoshisuke Ban, Shinobu Ohya +1
We report the annealing-induced enhancement of ferromagnetism and nano-particle formation in group-IV-based ferromagnetic-semiconductor GeFe. We successfully increase the Curie tem…