PAPERS

2024

Observation of converse flexoelectric effect in topological semimetals

Hidefumi Takahashi, Yusuke Kurosaka, Kenta Kimura, Akitoshi Nakano, Shintaro Ishiwata
Commun. Mater., 5, 236 (2024)

Dimensionality-driven power-law gap in the bilayer TaTe2 grown by molecular-beam epitaxy

B. K. Saika, S. Yoshida, M. Pardo-Almanza, N. Mitsuishi, M. Sakano, Y. Fujisawa, Y. Wang, Y. Iwasa, H. Mitsuoka, H. Takahashi, S. Ishiwata, Y. Okada, M. Nakano, K. Ishizaka
APL Mater. , 12, 071105 (2024)

Negative charge-transfer energy in SrFeO3 revisited with hard x-ray photoemission spectroscopy

D. Takegami, M. Nakamura, A. Melendez-Sans, K. Fujinuma, R. Nakamura, M. Yoshimura, K.-D. Tsuei, A. Tanaka, M. Gen, Y. Tokunaga, S. Ishiwata, and T. Mizokawa
Phys. Rev. B 109, 235138 (2024)

Multiband Metallic Ground State in Multilayered Nickelates La3Ni2O7 and La4Ni3O10 Probed by 139La-NMR at Ambient Pressure

M. Kakoi, T. Oi, Y. Ohshita, M. Yashima, K. Kuroki, T. Kato, H. Takahashi, S. Ishiwata, Y. Adachi, N. Hatada, T. Uda, and H. Mukuda
J. Phys. Soc. Jpn.,  93, 053702 (2024) [Selected as Editors’ Choice]

Large anomalous Hall effect in spin fluctuating devil’s staircase

Naoki Abe, Yuya Hano, Hiroaki Ishizuka, Yusuke Kozuka, Terumasa Tadano, Yoshihiro Tsujimoto, Kazunari Yamaura, Shintaro Ishiwata & Jun Fujioka
npj Quantum Materials, 9, 41 (2024)

Unusual photoinduced crystal structure dynamics in TaTe2 with double zigzag chain superstructure

J. Koga, Y. Chiashi, A. Nakamura, T. Akiba, H. Takahashi, T. Shimojima, S. Ishiwata, and K. Ishizaka
Applied Physics Express, 17
, 042007 (2024)

Unveiling the orbital-selective electronic band reconstruction through the structural phase transition in TaTe2

N. Mitsuishi, Y. Sugita, T. Akiba, Y. Takahashi, M. Sakano, K.i Horiba, H. Kumigashira, H. Takahashi, S. Ishiwata, Y. Motome, and K. Ishizaka
Phys. Rev. Res.
6, 013155 (2024)


2023

Superconductivity in a ferroelectric-like topological semimetal SrAuBi

H. Takahashi, T. Sasaki, A. Nakano, K. Akiba, M. Takahash, A. H. Mayo, M. Onose, T. C. Kobayashi, S. Ishiwata
npj Quantum Materials
8, 77 (2023) 

Ultrafast control of the crystal structure in a topological charge-density-wave material

T. Suzuki, Y. Kubota, N. Mitsuishi, S. Akatsuka, J. Koga, M. Sakano, S. Masubuchi, Y. Tanaka, T. Togashi, H. Ohsumi, K. Tamasaku, M. Yabashi, H. Takahashi, S. Ishiwata, T. Machida, I. Matsuda, K. Ishizaka, and K. Okazaki
Phys. Rev. B
108, 184305 (2023)

Real-Space Observation of Ligand Hole State in Cubic Perovskite SrFeO3

S. Kitou, M. Gen, Y. Nakamura, K. Sugimoto, Y. Tokunaga, S. Ishiwata, T. Arima
Advanced Science
2302839 (2023)

Observation of local atomic displacements intrinsic to the double zigzag chain structure of 1T-MTe2 (M = V, Nb, Ta)

N. Katayama, Y. Matsuda, K. Kojima, T. Hara, S. Kitou, N. Mitsuishi, H. Takahashi, S. Ishiwata, K. Ishizaka, and H. Sawa
Phys. Rev. B
107, 245113 (2023)

Machine learning of atomic force microscopy images of organic solar cells

Yasuhito Kobayashi, Yuta Miyake, Fumitaka Ishiwari, Shintaro Ishiwata, Akinori Saeki
RSC Advances,
 13, 15107 (2023)

Low-temperature phase transition in polar semimetal Td-MoTe2 probed by nonreciprocal transport

Y.M. Itahashi, Y. Nohara, T. Ideue, T. Akiba, H. Takahashi, S. Ishiwata, Y. Iwasa
Phys. Rev. Research,
 5, L022022 (2023)

Superconductivity in a magnetic Rashba semimetal EuAuBi

H. Takahashi,  K. Akiba, M. Takahashi, A. H. Mayo, M. Ochi, T. C. Kobayashi, S. Ishiwata
J. Phys. Soc. Jpn.
92, 013701 (2023) [Selected as Editors’ Choice and Hot Topic]


2022

Enhancement of the magnetoresistance in the mobility-engineered compensated metal Pt5P2

Alex H. Mayo, Hidefumi Takahashi,  Shintaro Ishiwata, Karolina Górnicka, Michał J. Winiarski, Jan Jaroszynski, Robert J. Cava, Weiwei Xie, Tomasz Klimczuk
Adv. Elec. Mater.
2201120 (2022)

Possible helimagnetic order in Co4+-containing perovskites Sr1−xCaxCoO3

H. Takahashi,  M. Onose, Y. Kobayashi, T. Osaka, S. Maeda, A. Miyake, M. Tokunaga, H. Sagayama, Y. Yamasaki, S. Ishiwata
APL Materials 10, 111116 (2022) [invited article for the Special Topic on “Materials Challenges and Synthesis Science of Emerging Quantum Materials”]

Spin-charge coupling and decoupling in perovskite-type iron oxides (Sr1-xBax)2/3La1/3FeO3

M. Onose, H. Takahashi,  T. Saito, T. Kamiyama, R. Takahashi, H. Wadati, S. Kitao, M. Seto, H. Sagayama, Y. Yamasaki, T. Sato , F. Kagawa, S. Ishiwata
Phys. Rev. Mater. 6, 094401 (2022)

When Superconductivity Loves Polarity

Shintaro Ishiwata
JPSJ News Comments 19, 09 (2022)

Spin-orbit-derived giant magnetoresistance in a layered magnetic semiconductor AgCrSe2

H. Takahashi, T. Akiba, A. H. Mayo, K. Akiba, A. Miyake, M. Tokunaga, H. Mori, R. Arita, S. Ishiwata
Phys. Rev. Mater.
6, 054602 (2022) [selected as Editors’ Suggestion]

Magnetic generation and switching of topological quantum phases in a trivial semimetal α-EuP3

A. H. Mayo, H. Takahashi, M. S. Bahramy, A. Nomoto, H. Sakai, S. Ishiwata
Phys. Rev. X 12
, 011033 (2022)

“Role of Spin-Spiral Period for Anomalous Magnetic-Field-Induced Spectral Variation of Electromagnon Resonance in Multiferroic Ba2Mg2Fe12O22”

Hiroe Shishikura, Sintaro Ishiwata, Yasujiro Taguchi, Yoshinori Tokura, Youtarou Takahashi
J. Phys. Soc. Jpn. 91, 033701 (2022)


2021

High-Pressure Synthesis of a Massive and Non-Symmorphic Dirac Semimetal Candidate MoP4

A. H. Mayo, J. A. Richards, H. Takahashi, S. Ishiwata
J. Phys. Soc. Jpn.  90, 123704 (2021) [Selected as Editors’ Choice and Hot Topic]

“Variation of charge dynamics upon antiferromagnetic transitions in the Dirac semimetal EuMnBi2”

H. Nishiyama, H. Sakai, K. Nakagawa, N. Hanasaki, S. Ishiwata, H. Masuda, M. Ochi, K. Kuroki, S. Iguchi, T. Sasaki, Y. Ikemoto, T. Moriwaki, K. Ueda, Y. Tokura, J. Fujioka
Phys. Rev. B 104, 115111 (2021)

“High-pressure synthesis of Ba2RhO4, a rhodate analogue of the layered perovskite Sr-ruthenate”

I. Kurata, José A. Flores-Livas, H. Sugimoto, H. Takahashi, H. Sagayama, Y. Yamasaki, T. Nomoto, R. Arita, S. Ishiwata
Phys. Rev. Mater. 5, 015001 (2021), arXiv:2010.06556


2020

“Structure analysis of high-pressure phase for skyrmion-hosting multiferroic Cu2OSeO3”

E. Nishibori, S. Karatsu, C. Terakura, N. Takeshita, M. Kinoshita, S. Ishiwata, Y. Tokura, S. Seki
Phys. Rev. B  102, 201106(R) (2020), arXiv:2009.07577

“Complete phase diagram of Sr1-xLaxFeO3 with versatile magnetic and charge ordering”

M. Onose, H. Takahashi, H. Sagayama, Y. Yamasaki, and S. Ishiwata
Phys. Rev. Mater. 4, 114420 (2020), arxiv.org/abs/2010.14966 

“Competing spin modulations in the magnetically frustrated semimetal EuCuSb”

Hidefumi Takahashi, Kai Aono, Yusuke Nambu, Ryoji Kiyanagi, Takuya Nomoto, Masato Sakano, Kyoko Ishizaka, Ryotaro Arita, Shintaro Ishiwata
Phys. Rev. B 102, 174425 (2020), arXiv:2010.06841 

“Nanoscale imaging of unusual photo-acoustic waves in thin flake VTe2”

Asuka Nakamura, Takahiro Shimojima, Yusuke Chiashi, Manabu Kamitani, Hideaki Sakai, Shintaro Ishiwata, Han Li, and Kyoko Ishizaka
Nano Lette
rs 20 , 4932-4938 (2020)

“Switching of band inversion and topological surface states by charge density wave”

N. Mitsuishi, Y. Sugita, M. S. Bahramy, M. Kamitani, T. Sonobe, M. Sakano, T. Shimojima, H. Takahashi, H. Sakai, K. Horiba, H. Kumigashira, K. Taguchi, K. Miyamoto, T. Okuda, S. Ishiwata, Y. Motome, and K. Ishizaka
Nat. Commun. 11, 2466 (2020). [selected as FOCUS]

“Large Magneto-piezoelectric Effect in EuMnBi2 Single Crystal at Low Temperatures”

Yuki Shiomi, Hidetoshi Masuda, Hidefumi Takahashi, and Shintaro Ishiwata
Sci. Rep. 10, 7574 (2020).

Prediction of perovskite-related structures in ACuO3-x (A = Ca, Sr, Ba, Sc, Y, La) using density functional theory and Bayesian optimization

Atsuto Seko and Shintaro Ishiwata
Phys. Rev. B
101, 134101 (2020) [selected as Editors’ Suggestion]

“Field-induced spin reorientation in the antiferromagnetic Dirac material EuMnBi2 revealed by neutron and resonant x-ray diffraction”

H. Masuda, H. Sakai, H. Takahashi, Y. Yamasaki, A. Nakao, T. Moyoshi, H. Nakao, Y. Murakami, T. Arima, and S. Ishiwata
Phys. Rev. B
101, 174411 (2020).

“Emergent topological spin structures in centrosymmetric cubic perovskite SrFeO3”

S. Ishiwata, T. Nakajima, J. -H. Kim, D. S. Inosov, N. Kanazawa, J. S. White, J. L. Gavilano, R. Georgii, K. M. Seemann, G. Brandl, P. Manuel, D. D. Khalyavin, S. Seki, Y. Tokunaga, M. Kinoshita, Y. W. Long, Y. Kaneko, Y. Taguchi, T. Arima, B. Keimer, and Y. Tokura
Phys. Rev.
B 101, 134406 (2020) [selected as Editors’ Suggestion]


2019

Giant enhancement of cryogenic thermopower by polar structural instability in a pressurized semimetal MoTe2

H. Takahashi, K. Hasegawa, T. Akiba, H. Sakai, M. S. Bahramy and S. Ishiwata
Phys. Rev. B
, 100, 195130 (2019).

High pressure synthesis of quasi-one-dimensional GdFeO3-type perovskite PrCuO3 with nearly divalent Cu ions

M. Ito, H. Takahashi, H. Sakai, H. Sagayama, Y. Yamasaki, Y. Yokoyama, H. Setoyama, H. Wadati, K. Takahashi, Y. Kusano and S. Ishiwata
Chem. Commun.
, 55, 8931 (2019) [Invited Feature Article for “Perovskites”]

“Observation of a Magnetopiezoelectric Effect in the Antiferromagnetic Metal EuMnBi2”

Y. Shiomi, H. Watanabe, H. Masuda,  H. Takahashi, Y. Yanase, and S. Ishiwata
Phys. Rev. Lett. 122, 127207 (2019).


2018

Impact of antiferromagnetic order on Landau level splitting of quasi-two-dimensional Dirac fermions in EuMnBi2” 

H. Masuda, H.Sakai, M. Tokunaga, M. Ochi, H. Takahashi, K. Akiba, A. Miyake, K. Kuroki, Y. Tokura, S. Ishiwata
Phys. Rev. B 98, 161108(R) (2018).

Negative-pressure-induced helimagnetism in ferromagnetic cubic perovskites Sr1-xBaxCoO3” 

H. Sakai, S. Yokoyama, A. Kuwabara, J. S. White, E. Canevet, H. M. Ronnow, T. Koretsune, R. Arita, A. Miyake, M. Tokunaga, Y. Tokura, S. Ishiwata 
Phys. Rev. Mater. 2, 104412 (2018).
OPEN ACCESS

“Giant Piezoelectric Response in Superionic Polar Semiconductor” 

Y. Shiomi, T. Akiba, H. Takahashi, S. Ishiwata 
Adv. Electron. Mater. 1800174(2018).

“Evaluation of photo-induced shear strain in monoclinic VTe2 by ultrafast electron diffraction” 

A. Nakamura, T. Shimojima, M. Matsuura, Y. Chiashi, M. Kamitani, H. Sakai, S. Ishiwata, H. Li, A. Oshiyama, K. Ishizaka 
Appl. Phys. Express 11, 092601 (2018).

“Enhanced thermopower via spin-state modification” 

H. Takahashi, S.Ishiwata, R. Okazaki, Y. Yasui, and I. Terasaki 
Phys. Rev. B 98, 024405 (2018).

「SACLAを用いた時間分解透過型X線回折による1T’-MoTe2の格子ダイナミクス観測」

下志万貴博,中村飛鳥,石坂香子,田中良和,田久保耕,平田靖透,和達大樹,山本達,松田巌,池浦晃至,高橋英史,酒井英明,石渡晋太郎,富樫格,大和田成起,片山哲夫,登野健介,矢橋牧名,辛埴 
X線分析の進歩 49, (2018).


2017

“Optical Magnetoelectric Resonance in a Polar Magnet (Fe,Zn)2Mo3O8 with Axion-Type Coupling” 

T. Kurumaji, Y. Takahashi, J. Fujioka, R. Masuda, H. Shishikura, S. Ishiwata, and Y. Tokura 
Phys. Rev. Lett. 119, 077206 (2017).

“Giant thermal Hall effect in multiferroics” 

T. Ideue, T.Kurumaji, S. Ishiwata, Y. Tokura 
Nat. Mater. 16, 797 (2017).

“High-pressure synthesis of an unusual antiferromagnetic metal CaCoO3 with GdFeO3-type perovskite structure”

T. Osaka, H. Takahashi, H. Sagayama, Y. Yamasaki, and S. Ishiwata 
Phys. Rev. B  95, 224440 (2017)

“Electromagnon resonance in a collinear spin state of the polar antiferromagnet Fe2Mo3O8” 

T. Kurumaji, Y. Takahashi, J. Fujioka, R. Masuda, H. Shishikura, S. Ishiwata, and Y. Tokura 
Phys. Rev. B  95, 020405 (2017)

“Diagonal magnetoelectric susceptibility and effect of Fe doping in the polar ferrimagnet Mn2Mo3O8”

T. Kurumaji, S. Ishiwata, and Y. Tokura 
Phys. Rev. B  95, 045142 (2017)

“Observation of spin-polarized bands and domain-dependent Fermi arcs in polar Weyl semimetal MoTe2”

M. Sakano, M. S. Bahramy, H. Tsuji, I. Araya, K. Ikeura, H. Sakai, S. Ishiwata, K. Yaji, K. Kuroda, A. Harasawa, S. Shin, and K. Ishizaka 
Phys. Rev. B  95, 121101(R) (2017)

“Anticorrelation between polar lattice instability and superconductivity in the Weyl semimetal candidate MoTe2”

H. Takahashi, T. Akiba, K. Imura, T. Shiino, K. Deguchi, N. K. Sato, H. Sakai, M. S. Bahramy, and S. Ishiwata
Phys. Rev. B  95, 100501(R) (2017)


2016

“Critical enhancement of thermopower in a chemically tuned polar semimetal MoTe2”

H. Sakai, K. Ikeura, M. S. Bahramy, N. Ogawa, D. Hashizume, J. Fujioka, Y. Tokura, and S. Ishiwata
Science Advances 2, e1601378 (2016).

“Contrasting magnetic behaviors in Rh- and Ru-doped cubic perovskite SrFeO3: nearly ferromagnetic metal vs. spin-glass insulator”

M. Kinoshita, H. Sakai, N. Hayashi, Y. Tokura, M. Takano, and S. Ishiwata 
Angew. Chem. Int. Ed. 55, 15292 (2016).

“Relation between the structural phase transition and superconductivity in CuxIrTe2-ySey”

M. Kamitani, H. Sakai, Y. Tokura, and S. Ishiwata 
Phys. Rev. B 94, 134507 (2016).

“Colossal Seebeck effect enhanced by quasi-ballistic phonons dragging massive electrons in FeSb2”

H. Takahashi, R. Okazaki, S. Ishiwata, H. J. Taniguchi, A. Okutani, M. Hagiwara, and I. Terasaki. 
Nature Communications 7, 12732 (2016).

“Magnetic Reversal of Electric Polarization with Fixed Chirality of Magnetic Structure in a Chiral-Lattice Helimagnet MnSb2O6”

M. Kinoshita, S. Seki, T. J. Sato, Y. Nambu, T.Hong, M. Matsuda, H. B. CaO, S. Ishiwata, and Y. Tokura. 
Phys. Rev. Lett. 117, 047201 (2016).

“Revealing the ultrafast light-to-matter energy conversion before heat diffusion in a layered Dirac semimetal”

Y. Ishida, H. Masuda, H. Sakai,  S. Ishiwata, and S. Shin. 
Phys. Rev. B 93, 100302(R) (2016).

“Quantum Hall effect in a bulk antiferromagnet EuMnBi2 with magnetically confined two-dimensional Dirac fermions”

H. Masuda, H. Sakai, M. Tokunaga, Y. Yamasaki, A. Miyake, J. Shiogai, S. Nakamura, S. Awaji, A. Tsukazaki, H. Nakao, Y. Murakami, T. Arima, Y. Tokura, and S. Ishiwata. 
Science Advances 2, e1501117 (2016).

“Electromagnon excitation in the field-induced noncollinear ferrimagnetic phase of Ba2Mg2Fe12O22 studied by polarized inelastic neutron scattering and terahertz time-domain optical spectroscopy”

T. Nakajima, Y. Takahashi, S. Kibayashi, M. Matsuda, K. Kakurai, S. Ishiwata, Y. Taguchi, Y. Tokura, and T. Arima 
Phys. Rev. B 93, 035119 (2016).


2015

“Doping-Tunable Ferrimagnetic Phase with Large Linear Magnetoelectric Effect in a Polar Magnet Fe2Mo3O8”

T. Kurumaji, S. Ishiwata, and Y. Tokura 
Phys. Rev. X 5, 031034 (2015).

“Observation of a Devil’s Staircase in the Novel Spin-Valve System SrCo6O11”

T. Matsuda, S. Partzsch, T. Tsuyama, E. Schierle, E. Weschke, J. Geck, T. Saito, S. Ishiwata, Y. Tokura, and H. Wadati 
Phys. Rev. Lett. 114, 236403 (2015).

“Intrinsic effects of substitution and intercalation on thermal transport in two-dimensional TiS2 single crystals”

R. Daou, H. Takahashi, S. Hebert, M. Beaumale, E. Guilmeau, and A. Maignan. 
Journal of Applied Physics 117, 165101 (2015).

“Rich structural phase diagram and thermoelectric properties of layered tellurides Mo1-xNbxTe2”

K. Ikeura, H. Sakai, M. S. Bahramy and S. Ishiwata 
APL Mat. 3, 041514 (2015).


2014

“Anomalous domain-wall conductance in pyrochlore-type Nd2Ir2O7 on the verge of the metal-insulator transition”

K. Ueda, J. Fujioka, Y. Takahashi, T. Suzuki, S. Ishiwata, Y. Taguchi, M. Kawasaki, and Y. Tokura 
Phys. Rev. B 89, 075127 (2014).

“Insulator-to-Superconductor Transition upon Electron Doping in a BiS2-Based Superconductor Sr1-xLaxFBiS2”

H. Sakai, D. Kotajima, K. Saito, H. Wadati, Y. Wakisaka, M. Mizumaki, K. Nitta, Y. Tokura, and S. Ishiwata 
J. Phys. Soc. Jpn. 83, 014709 (2014). (Selected as Editors’ Choice)


2013

“Microwave magnetoelectric effect via skyrmion resonance modes in a helimagnetic multiferroic”

Y. Okamura, F. Kagawa, M. Mochizuki, M. Kubota, S. Seki, S. Ishiwata, M. Kawasaki, Y. Onose and Y. Tokura 
Nature Commun. 4, 2391(6 pages) (2013).

“Multiple helimagnetic phases and topological Hall effect in epitaxial thin films of pristine and Co-doped SrFeO3”

S. Chakraverty, T. Matsuda, H. Wadati, J. Okamoto, Y. Yamasaki, H. Nakao, Y. Murakami, S. Ishiwata, M. Kawasaki, Y. Taguchi, Y. Tokura, and H. Y. Hwang 
Phys. Rev. B 88, 220405(R) (2013)

“Towards control of skyrmion crystals in helimagnetic alloys by spin-orbit coupling”

K. Shibata, X. Z. Yu, T. Hara, D. Morikawa, N. Kanazawa, K. Kimoto, S. Ishiwata, Y. Matsui and Y. Tokura 
Nature Nanotech. 8, 723 (2013).

“Optimal Tc for the electron-doped cuprate realized under high pressure”

S. Ishiwata, D. Kotajima, N. Takeshita, C. Terakura, S. Seki, Y. Tokura, 
J. Phys. Soc. Jpn. 82, 063705 (2013).

“Superconductivity in CuxIrTe2 driven by interlayer hybridization”

M. Kamitani, M. S. Bahramy, R. Arita, S. Seki, T. Arima, Y. Tokura, and S. Ishiwata, 
Phys. Rev. B 87, 180501(R) (2013). (Selected as Editors’ suggestion)

“Extremely high electron mobility in a phonon-glass semimetal”

S. Ishiwata, Y. Shiomi, J. S. Lee, M. S. Bahramy, T. Suzuki, M. Uchida, R. Arita, Y. Taguchi, and Y. Tokura 
Nat. Mater. 12, 512-517 (2013).

“Magnetoelectric responses induced by domain rearrangement and spin structural change in triangular-lattice helimagnets NiI2 and CoI2”

T. Kurumaji, S. Seki, S. Ishiwata, H. Murakawa, Y. Kaneko, and Y. Tokura 
Phys. Rev. B 87, 014429 (2013).


2012

“Possible skyrmion-lattice ground state in the B20 chiral-lattice magnet MnGe as seen via small-angle neutron scattering”

N. Kanazawa, J.-H. Kim, D. S. Inosov, J. S. White, N. Egetenmeyer, J. L. Gavilano, S. Ishiwata, Y. Onose, T. Arima, B. Keimer, and Y. Tokura 
Phys. Rev. B 86, 134425 (2012). (Selected as Editor’s suggestion)

“Variation of Charge Dynamics in the Course of Metal-Insulator Transition for Pyrochlore-type Nd2Ir2O7”

K. Ueda, J. Fujioka, Y. Takahashi, T. Suzuki, S. Ishiwata, Y. Taguchi, and Y. Tokura 
Phys. Rev. Lett. 109, 136402 (2012).

“Evolution of magnetic phases in single crystals of SrFe1-xCoxO3 solid solution”

Y. W. Long, Y. Kaneko, S. Ishiwata, Y. Tokunaga, T. Matsuda, H. Wadati, Y. Tanaka, S. Shin, Y. Tokura, and Y. Taguchi 
Phys. Rev. B 86, 064436 (2012).

“Magnetoelectric nature of skyrmions in a chiral magnetic insulator Cu2OSeO3”

S. Seki, S. Ishiwata, and Y. Tokura 
Phys. Rev. B 86, 060403 (2012).

“Observation of Magnetic Excitations of Skyrmion Crystal in a Helimagnetic Insulator Cu2OSeO3”

Y. Onose, Y. Okamura, S. Seki, S. Ishiwata, and Y. Tokura 
Phys. Rev. Lett. 109, 037603 (2012).

“Formation and rotation of skyrmion crystal in the chiral-lattice insulator Cu2OSeO3”

S. Seki, J.-H. Kim, D. S. Inosov, R. Georgii, S. Ishiwata, B. Keimer, and Y. Tokura 
Phys. Rev. B 85, 220406 (2012).

“Observation of Skyrmions in a Multiferroic Material”

S. Seki, X. Z. Yu, S. Ishiwata, and Y. Tokura 
Science 336, 198 (2012).

“Variation of charge dynamics upon the helimagnetic and metal-insulator transitions for perovskite AFeO3 (A=Sr and Ca)”

J. Fujioka, S. Ishiwata, Y. Kaneko, Y. Taguchi, and Y. Tokura 
Phys. Rev. B 85, 155141 (2012).

“Effect of lattice geometry on magnon Hall effect in ferromagnetic insulators”

T. Ideue, Y. Onose, H. Katsura, Y. Shiomi, S. Ishiwata, N. Nagaosa, and Y. Tokura 
Phys. Rev. B 85, 134411 (2012). (Selected as Editor’s suggestion)

“Band-filling dependence of thermoelectric properties in B20-type CoGe”

N. Kanazawa Y. Onose, Y. Shiomi, S. Ishiwata, and Y. Tokura 
Appl. Phys. Lett. 100, 093902 (2012).

“Topological Hall effect in pyrochlore lattice with diluted spin chirality”

K. Ueda, S. Iguchi, T. Suzuki, S. Ishiwata, Y. Taguchi, and Y. Tokura 
Phys. Rev. Lett. 108, 156601 (2012).

“Emergent phenomena in perovskite-type manganites”

Y. Taguchi, H. Sakai, D. Okuyama, S. Ishiwata, J. Fujioka, T. Fukuda, D. Hashizume, F. Kagawa, Y. Takahashi, R. Shimano, Y.Tokunaga, Y.Kaneko, A.Nakao, H. Nakao, Y. Murakami, K.Sugimoto, M.Takata, K.Yamauchi, S.Picozzi, A.Q.R.Baron, T. Arima, Y. Tokura 
Phys. Rev. Lett. 108, 156601 (2012).


2011

“High-Pressure Hydrothermal Crystal Growth and Multiferroic Properties of a Perovskite YMnO3”

S. Ishiwata, Y. Tokunaga, Y. Taguchi, and Y. Tokura 
J. Am. Chem. Soc. 133, 13818–13820 (2011) (Communication)

“Mott insulator to metal transition in filling-controlled SmMnAsO1−x”

Y. Shiomi, S. Ishiwata, Y. Taguchi, and Y. Tokura 
Phys. Rev. B.84, 054519 (2011) (Selected as Editor’s suggestion)

“Magnetically-Driven Ferroelectric Atomic Displacements in perovskite like YMnO3”

D. Okuyama, S. Ishiwata, Y. Takahashi, K. Yamauchi, S. Picozzi, K. Sugimoto, H. Sakai, M. Takata, R. Shimano, Y. Taguchi, T. Arima, and Y. Tokura 
Phys. Rev. B.84, 054440 (2011)

“Versatile helimagnetic phases under magnetic fields in cubic perovskite SrFeO3”

S. Ishiwata, M. Tokunaga, Y. Kaneko, D. Okuyama, Y. Tokunaga, S. Wakimoto, K. Kakurai, T. Arima, Y. Taguchi, and Y. Tokura 
Phys. Rev. B. 84, 054427 (2011)

“Colossal negative thermal expansion in BiNiO3 induced by intermetallic charge transfer”

M. Azuma, Wei-tin Chen, H. Seki, M. Czapski, S. Olga, K. Oka, M. Mizumaki, T. Watanuki, N. Ishimatsu, N. Kawamura, S. Ishiwata, M. G. Tucker, Y. Shimakawa and J. P. Attfield 
Nature Commun. 2, 347 (2011).

“Synthesis of cubic SrCoO3 single crystal and its anisotropic magnetic and transport properties”

Y. Long, Y. Kaneko, S. Ishiwata, Y. Taguchi, Y. Tokura 
J. Phys.: Condens. Matter  23, 245601 (2011).

“Large topological Hall effect in a short-period helimagnet MnGe”

N. Kanazawa, Y. Onose, T. Arima, D. Okuyama, K. Ohoyama, S. Wakimoto, K. Kakurai, S. Ishiwata, and Y. Tokura 
Phys. Rev. Lett. 106, 156603 (2011).

“Magnetic-field induced competition of two multiferroic orders in a triangular-lattice helimagnet MnI2”

T. Kurumaji, S. Seki, S. Ishiwata, H. Murakawa, Y. Tokunaga, Y. Kaneko, and Y. Tokura 
Phys. Rev. Lett. 106, 167206 (2011).

“Orbital Ordering of Intermediate-Spin State of Co3+ in Sr3YCo4O10.5 “

H. Nakao, T. Murata, D. Bizen , Y. Murakami, K. Ohoyama, K. Yamada, S. Ishiwata, W. Kobayashi, and I. Terasaki 
J. Phys. Soc. Jpn. 80, 023711 (2011) (Selected as Editors’ Choice)

“Gigantic terahertz magnetochromism via electromagnons in the hexaferrite magnet Ba2Mg2Fe12O22”

N. Kida, S. Kumakura, S. Ishiwata, Y. Taguchi, Y. Tokura 
Phys. Rev. B 83, 064422 (2011).

“Uniaxial Colossal Magnetoresistance in the Ising Magnet SrCo12O19”

S. Ishiwata, T. Nakano, I. Terasaki, Y. Uwatoko, H. Nakao, Y. Murakami, M. Takano 
Phys. Rev. B  83, 020401(R) (2011).

“Near room-temperature formation of a skyrmion crystal in thin-films of the helimagnet FeGe”

X. Z. Yu, N. Kanazawa, Y. Onose, K. Kimoto, W.Z. Zhang, S. Ishiwata, Y. Matsui, and Y. Tokura 
Nature Materials 10, 106-109 (2011).


2010

“Multiferroic M-type hexaferrites with room-temperature conical state and magnetically controllable spin helicity”

Y. Tokunaga, Y. Kaneko, D. Okuyama, S. Ishiwata, T. Arima, S. Wakimoto, K. Kakurai, Y. Taguchi, and Y. Tokura 
Physical Review Letters, 105, 257201 (2010).

“Electrons doped in cubic perovskite SrMnO3: isotropic metal versus chainlike ordering of Jahn-Teller polarons”

H. Sakai, S. Ishiwata, D. Okuyama1 , A. Nakao, H. Nakao, Y. Murakami, Y. Taguchi, and Y. Tokura 
Phys. Rev. B  82, 180409(R) (2010).

“Synthesis, Structure, and Physical Properties of A-site Ordered Perovskites ACu3Co4O12 (A=Ca and Y)”

I. Yamada, S. Ishiwata, I. Terasaki, M. Azuma, Y. Shimakawa, and M. Takano 
Chem. Mater. 22, 5328 (2010).

“Cupric chloride CuCl2 as an S = 1/2 chain multiferroic”

S. Seki, T. Kurumaji, S. Ishiwata, H. Matsui, H. Murakawa, Y. Tokunaga, Y. Kaneko, T. Hasegawa, and Y. Tokura 
Phys. Rev. B 82, 064424 (2010).

“Neutron diffraction studies on the multiferroic conical magnet Ba2Mg2Fe12O22”

S. Ishiwata, D. Okuyama, K. Kakurai, M. Nishi, Y. Taguchi, Y. Tokura, 
Phys. Rev. B, 81, 174418 (2010)

“Electromagnons in the multiferroic state of perovskite manganites with symmetric exchange striction”

Y. Takahashi, S. Ishiwata, S. Miyahara, Y. Kaneko, N. Furukawa, Y. Taguchi, R. Shimano, and Y. Tokura 
Phys. Rev. B 81, 100413(R) (2010)

“Perovskite Manganites Hosting Versatile Multiferroic Phases with Symmetric and Antisymmetric Exchange Strictions”

S. Ishiwata, Y. Kaneko, Y. Tokunaga, Y. Taguchi, T. Arima, and Y. Tokura 
Phys. Rev. B 81, 100411(R) (2010)

“Single crystal growth and structure of La4Cu3MoO12”

J. A. Enterkin, P. A. Maggard, S. Ishiwata, L. D. Marks, K. R. Poeppelmeier, M. Azuma, M. Takano 
J. Solid State Chem. 183, 551-556 (2010).