119 citations · 1.5k across the 44 of their papers we have counts for
24 papers · 1 filter
Structural insight using anomalous XRD into Mn2CoAl Heusler alloy films grown by magnetron sputtering, IBAS and MBE techniques
Hiroo Tajiri, Loku Singgappulige Rosantha Kumara, Yuya Sakuraba +8
Inverse Heusler alloy Mn2CoAl thin films, known as a spin-gapless semiconductor (SGS), grown by three different methods: ultra-high vacuum magnetron spattering, Ar-ion beam assiste…
Anomalous Hall conductivity and electronic structures of Si-substituted MnCoAl epitaxial films
K. Arima, F. Kuroda, S. Yamada +3
We study anomalous Hall conductivity () and electronic band structures of Si-substituted MnCoAl (MnCoAlSi). First-principles calculations r…
Room-temperature spin transport in n-Ge probed by four-terminal nonlocal measurements
Michihiro Yamada, Makoto Tsukahara, Yuichi Fujita +4
We demonsrtate electrical spin injection and detection in -type Ge (-Ge) at room temperature using four-terminal nonlocal spin-valve and Hanle-effect measurements in lateral…
Spin injection into multilayer graphene from highly spin-polarized Co2FeSi Heusler alloy
Takehiro Yamaguchi, Rai Moriya, Yoichiro Oki +4
We demonstrate electrical spin injection into multilayer graphene (MLG) in a lateral spin valve device from a highly spin-polarized Co2FeSi (CFS) Huesler electrode. Exfoliated MLG…
Direct Evidence for Suppression of the Kondo Effect due to Pure Spin Current
K. Hamaya, T. Kurokawa, S. Oki +3
We study the effect of a pure spin current on the Kondo singlet in a diluted magnetic alloy using non-local lateral spin valve structures with highly spin polarized Co2FeSi electro…
Exchange-driven magnetoresistance in silicon facilitated by electrical spin injection
Yuichiro Ando, Lan Qing, Yang Song +6
We use electrical spin injection to probe exchange interactions in phosphorus doped silicon (Si:P). The detection is enabled by a magnetoresistance effect that demonstrates the eff…
Large enhancement in the generation efficiency of pure spin currents in Ge using Heusler-compound Co_2FeSi electrodes
K. Kasahara, Y. Fujita, S. Yamada +3
We show nonlocal spin transport in n-Ge based lateral spin-valve devices with highly ordered Co_2FeSi/n^+-Ge Schottky tunnel contacts. Clear spin-valve signals and Hanle-effect cur…
Giant enhancement of spin pumping efficiency using Fe3Si ferromagnet
Y. Ando, K. Ichiba, S. Yamada +4
Spincurrentronics, which involves the generation, propagation and control of spin currents, has attracted a great deal of attention because of the possibility of realizing dissipat…
Dynamical Spin Injection into p-type Germanium at Room Temperature
Mariko Koike, Eiji Shikoh, Yuichiro Ando +4
We demonstrate dynamical spin injection into p-type germanium (Ge) at room temperature (RT) using spin pumping. The generated pure spin current is converted to a charge current by…
Effect of Co-Fe substitutions on the room-temperature spin polarization in Co_3-xFe_xSi Heusler-compound films
K. Tanikawa, S. Oki, S. Yamada +3
Using low-temperature molecular beam epitaxy, we study substitutions of Fe atoms for Co ones in Co_3-xFe_xSi Heusler-compound films grown on Si and Ge. Even for the low-temperature…
Room-temperature detection of spin accumulation in silicon across Schottky tunnel barriers using a MOSFET structure
K. Hamaya, Y. Ando, K. Masaki +5
Using a metal-oxide-semiconductor field effect transistor (MOSFET) structure with a high-quality CoFe/n^+Si contact, we systematically study spin injection and spin accumulation in…
Atomically Controlled Epitaxial Growth of Single-Crystalline Germanium Films on a Metallic Silicide
S. Yamada, K. Tanikawa, M. Miyao +1
We demonstrate high-quality epitaxial germanium (Ge) films on a metallic silicide, Fe3Si, grown directly on a Ge(111) substrate. Using molecular beam epitaxy techniques, we can obt…
Effect of the magnetic domain structure in the ferromagnetic contact on spin accumulation in silicon
Y. Ando, S. Yamada, K. Kasahara +3
We show a marked effect of the magnetic domain structure in an epitaxial CoFe contact on the spin accumulation signals in Si detected by three-terminal Hanle-effect measurements. C…
Evidence for the Presence of Spin Accumulation in Localized States at Ferromagnet-Silicon Interfaces
Y. Ando, S. Yamada, K. Kasahara +4
We experimentally show evidence for the presence of spin accumulation in localized states at ferromagnet-silicon interfaces, detected by electrical Hanle effect measurements in CoF…
Spin accumulation created electrically in an n-type germanium channel using Schottky tunnel contacts
K. Kasahara, Y. Baba, K. Yamane +6
Using high-quality FeSi/-Ge Schottky-tunnel-barrier contacts, we study spin accumulation in an -type germanium (-Ge) channel. In the three- or two-terminal volta…
Bias current dependence of spin accumulation signals in a silicon channel detected by a Schottky tunnel contact
Y. Ando, K. Kasahara, K. Yamane +6
We study the electrical detection of spin accumulation at a ferromagnet-silicon interface, which can be verified by measuring a Hanle effect in three-terminal lateral devices. The…
Epitaxial Growth of a Full-Heusler Alloy CoFeSi on Silicon by Low-Temperature Molecular Beam Epitaxy
S. Yamada, K. Yamamoto, K. Ueda +4
For electrical spin injection and detection of spin-polarized electrons in silicon, we explore highly epitaxial growth of ferromagnetic full-Heusler-alloy Co2FeSi thin films on sil…
Ferromagnetism and Electronic Structures of Nonstoichiometric Heusler-Alloy Fe_3-xMn_xSi Epilayers Grown on Ge(111)
K. Hamaya, H. Itoh, O. Nakatsuka +6
For the study of ferromagnetic materials which are compatible with group-IV semiconductor spintronics, we demonstrate control of the ferromagnetic properties of Heusler-alloys Fe_3…
Epitaxial ferromagnetic FeSi/Si(111) structures with high-quality hetero-interfaces
K. Hamaya, K. Ueda, Y. Kishi +3
To develop silicon-based spintronic devices, we have explored high-quality ferromagnetic FeSi/silicon (Si) structures. Using low-temperature molecular beam epitaxy at 130 $^c…
Magnetic anisotropy switching in (Ga,Mn)As with increasing hole concentration
K. Hamaya, T. Watanabe, T. Taniyama +3
We study a possible mechanism of the switching of the magnetic easy axis as a function of hole concentration in (Ga,Mn)As epilayers. In-plane uniaxial magnetic anisotropy along [11…
Dynamic relaxation of magnetic clusters in a ferromagnetic (Ga,Mn)As epilayer
K. Hamaya, T. Koike, T. Taniyama +3
A new scenario of the mechanism of intriguing ferromagnetic properties in Mn-doped magnetic semiconductor (Ga,Mn)As is examined in detail. We find that magnetic features seen in ze…
Ion Irradiation Control of Ferromagnetism in (Ga,Mn)As
H. Kato, K. Hamaya, T. Taniyama +2
We report on a promising approach to the artificial modification of ferromagnetic properties in (Ga,Mn)As using a Ga focused ion beam (FIB) technique. The ferromagnetic propert…
Effect of Ga irradiation on magnetic and magnetotransport properties in (Ga,Mn)As epilayers
H. Kato, K. Hamaya, Y. Kitamoto +2
We report on the magnetic and magnetotransport properties of ferromagnetic semiconductor (Ga,Mn)As modified by Ga ion irradiation using focused ion beam. A marked reduction i…
Current-induced magnetization reversal in a (Ga,Mn)As-based magnetic tunnel junction
R. Moriya, K. Hamaya, A. Oiwa +1
We report current-induced magnetization reversal in a ferromagnetic semiconductor-based magnetic tunnel junction (Ga,Mn)As/AlAs/(Ga,Mn)As prepared by molecular beam epitaxy on a p-…