start-ver=1.4
cd-journal=joma
no-vol=109
cd-vols=
no-issue=17
article-no=
start-page=174503
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2024
dt-pub=20240502
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Time-dependent Ginzburg-Landau theory of the vortex spin Hall effect
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=We develop a time-dependent Ginzburg-Landau theory of the vortex spin Hall effect, i.e., a spin Hall effect that is driven by the motion of superconducting vortices. For the direct vortex spin Hall effect in which an input charge current drives the transverse spin current accompanying the vortex motion, we start from the well-known Schmid-Caroli-Maki solution for the time-dependent Ginzburg-Landau equation under the applied electric field, and find out the expression of the induced spin current. For the inverse vortex spin Hall effect in which an input spin current drives the longitudinal vortex motion and produces the transverse charge current, we microscopically construct the time-dependent Ginzburg-Landau equation under the applied spin accumulation gradient, and calculate the induced transverse charge current as well as the open circuit voltage. The time-dependent Ginzburg-Landau equation and its analytical solution developed here can be a basis for more quantitative numerical simulations of the vortex spin Hall effect.
en-copyright=
kn-copyright=

en-aut-name=AdachiHiroto
en-aut-sei=Adachi
en-aut-mei=Hiroto
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=KatoYusuke
en-aut-sei=Kato
en-aut-mei=Yusuke
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=OheJun-ichiro
en-aut-sei=Ohe
en-aut-mei=Jun-ichiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=IchiokaMasanori
en-aut-sei=Ichioka
en-aut-mei=Masanori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=2
en-affil=Department of Basic Science, University of Tokyo
kn-affil=

affil-num=3
en-affil=Department of Physics, Toho University
kn-affil=

affil-num=4
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=
END

start-ver=1.4
cd-journal=joma
no-vol=107
cd-vols=
no-issue=15
article-no=
start-page=155142
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2023
dt-pub=20230425
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Ginzburg-Landau action and polarization current in an excitonic insulator model of electronic ferroelectricity
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=In comparison to transport of spin polarization in ferromagnets, transport of electric polarization in ferroelectrics remains less explored. Taking an excitonic insulator model of electronic ferroelectricity as a prototypical example, we theoretically investigate the low-energy dynamics and transport of electric polarization by microscopically constructing the Ginzburg-Landau action. We show that, because of the scalar nature of the excitonic order parameter, only the longitudinal fluctuations are relevant to the transport of electric polarization. We also formulate the electric-polarization diffusion equation, in which the electric-polarization current is defined purely electronically without recourse to the lattice degrees of freedom.
en-copyright=
kn-copyright=

en-aut-name=AdachiHiroto
en-aut-sei=Adachi
en-aut-mei=Hiroto
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=IkedaNaoshi
en-aut-sei=Ikeda
en-aut-mei=Naoshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=SaitohEiji
en-aut-sei=Saitoh
en-aut-mei=Eiji
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

affil-num=1
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=2
en-affil=Department of Physics, Okayama University
kn-affil=

affil-num=3
en-affil=Department of Applied Physics, The University of Tokyo
kn-affil=
END

start-ver=1.4
cd-journal=joma
no-vol=105
cd-vols=
no-issue=10
article-no=
start-page=104417-1
end-page=104417-14
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2022
dt-pub=2022315
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Antiferromagnetic spin Seebeck effect across the spin-flop transition: A stochastic Ginzburg-Landau simulation
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=We investigate the antiferromagnetic spin Seebeck effect across the spin-flop transition in a numerical simulation based on the time-dependent Ginzburg-Landau equation for a bilayer of a uniaxial insulating antiferromagnet and an adjacent metal. By directly simulating the rate of change of the conduction-electron spin density s in the adjacent metal layer, we demonstrate that a sign reversal of the antiferromagnetic spin Seebeck effect across the spin-flop transition occurs when the interfacial coupling of s to the staggered magnetization n of the antiferromagnet dominates, whereas no sign reversal appears when the interfacial coupling of s to the magnetization m dominates. Moreover, we show that the sign reversal is influenced by the degree of spin dephasing in the metal layer. Our result indicates that the sign reversal is not a generic property of a simple uniaxial antiferromagnet, but controlled by microscopic details of the exchange coupling at the interface and the spin dephasing in the metal layer.
en-copyright=
kn-copyright=

en-aut-name=YamamotoYutaka
en-aut-sei=Yamamoto
en-aut-mei=Yutaka
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=IchiokaMasanori
en-aut-sei=Ichioka
en-aut-mei=Masanori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=AdachiHiroto
en-aut-sei=Adachi
en-aut-mei=Hiroto
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

affil-num=1
en-affil=Department of Physics, Okayama University
kn-affil=

affil-num=2
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=3
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=
END

start-ver=1.4
cd-journal=joma
no-vol=12
cd-vols=
no-issue=1
article-no=
start-page=175
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2020
dt-pub=20200118
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Relation of Superconducting Pairing Symmetry and Non-Magnetic Impurity Effects in Vortex States
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Non-magnetic impurity scattering effects on the vortex core states are theoretically studied to clarify the contributions from the sign-change of the pairing function in anisotropic superconductors. The vortex states are calculated by the Eilenberger theory in superconductors with px-wave pairing symmetry, as well as the corresponding anisotropic s-wave symmetry. From the spatial structure of the pair potential and the local electronic states around a vortex, we examine the differences between anisotropic superconductors with and without sign-change of the pairing function, and estimate how twofold symmetric vortex core images change with increasing the impurity scattering rate both in the Born and the unitary limits. We found that twofold symmetric vortex core image of zero-energy local density of states changes the orientation of the twofold symmetry with increasing the scattering rate when the sign change occurs in the pairing function. Without the sign change, the vortex core shape reduces to circular one with approaching dirty cases. These results of the impurity effects are valuable for identifying the pairing symmetry by observation of the vortex core image by the STM observation.
en-copyright=
kn-copyright=

en-aut-name=SeraYasuaki
en-aut-sei=Sera
en-aut-mei=Yasuaki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=UedaTakahiro
en-aut-sei=Ueda
en-aut-mei=Takahiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=AdachiHiroto
en-aut-sei=Adachi
en-aut-mei=Hiroto
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=IchiokaMasanori
en-aut-sei=Ichioka
en-aut-mei=Masanori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=Department of Physics, Okayama University
kn-affil=

affil-num=2
en-affil=Department of Physics, Okayama University
kn-affil=

affil-num=3
en-affil=Department of Physics, Okayama University
kn-affil=

affil-num=4
en-affil=Department of Physics, Okayama University
kn-affil=
en-keyword=unconventional superconductivity
kn-keyword=unconventional superconductivity
en-keyword=pairing symmetry
kn-keyword=pairing symmetry
en-keyword=vortex states
kn-keyword=vortex states
en-keyword=non-magnetic impurity scattering
kn-keyword=non-magnetic impurity scattering
END