Fabrication of superlattice films of iron-based superconductors

• Project/Area Number: 15K17697
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Tohoku University (2016); The University of Tokyo (2015)
• Principal Investigator: Yoshinori Imai 東北大学, 理学研究科, 講師 (30435599)
• Research Collaborator: MAEDA Atsutaka 東京大学, 大学院総合文化研究科, 教授 (70183605) ; NABESHIMA Fuyuki 東京大学, 大学院総合文化研究科, 助教 (30782776)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2016: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2015: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 鉄系超伝導体 / 薄膜 / 人工超格子構造

Outline of Final Research Achievements

I investigated properties of FeSe1-xTex thin films and fabricated FeSe/FeTe superlattice thin films. In FeSe1-xTex films, structural transition temperature decreases with increasing x and the highest Tc is obtained at the composition where structural transition disappears.
In FeSe/FeTe superlattice films, x-ray diffraction patterns show clear satellite peaks demonstrating periodic stacking structures of FeSe and FeTe. The anisotropy of the upper critical field shows that the superconducting layer is not FeSe layer but FeTe layer because of the Se/Te interdiffusion at the interface.

Research Products

• [Journal Article] Growth and transport properties of FeSe/FeTe superlattice thin films (2017)
  • Author(s): F. Nabeshima, Y. Imai, A. Ichinose, I. Tsukada, A.Maeda
  • Journal Title: Jpn. J. Appl. Phys. Volume: 56 Issue: 2 Pages: 020308-020308
  • DOI: 10.7567/jjap.56.020308
  • NAID: 210000147413
  • Peer Reviewed
• [Journal Article] Control of structural transition in FeSe1-xTex thin films by changing substrate materials (2017)
  • Author(s): Yoshinori Imai, Yuichi Sawada, Fuyuki Nabeshima, Daisuke Asami, Masataka Kawai, Atsutaka Maeda
  • Journal Title: Sci. Rep. Volume: 7 Issue: 1
  • DOI: 10.1038/srep46653
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Gradual Fermi-surface modification in orbitally ordered state of FeSe revealed by optical spectroscopy (2017)
  • Author(s): M. Nakajima, K. Yanase, F. Nabeshima, Y. Imai, A. Maeda, S. Tajima
  • Journal Title: Phys. Rev. B Volume: 印刷中
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Investigation of Transport Properties for FeSe1-xTex Thin Films under Magnetic Fields. (2016)
  • Author(s): Y. Sawada, F. Nabeshima, Y. Imai, A. Maeda
  • Journal Title: J. Phys. Soc. Jpn. Volume: 85 Issue: 7 Pages: 073703-073703
  • DOI: 10.7566/jpsj.85.073703
  • NAID: 210000133988
  • Peer Reviewed
• [Journal Article] Superconducting properties of FeSe1-xTex films with x = 0－0.4. (2016)
  • Author(s): Y. Imai, Y. Sawada, D. Asami, F. Nabeshima, A. Maeda
  • Journal Title: Physica C Volume: 530 Pages: 24-26
  • DOI: 10.1016/j.physc.2016.05.001
  • Peer Reviewed
• [Journal Article] Transport properties of FeSe1-xTex thin films under magnetic fields up to 8 T. (2016)
  • Author(s): Y. Sawada, F. Nabeshima, D. Asami, R. Ogawa, Y. Imai, A. Maeda
  • Journal Title: Physica C Volume: 530 Pages: 27-30
  • DOI: 10.1016/j.physc.2016.02.020
  • Peer Reviewed
• [Journal Article] Origin of lattice compression of FeS1-xTex thin films on CaF2 substrates. (2016)
  • Author(s): I. Tsukada, A. Ichinose, F. Nabeshima, Y. Imai, A. Maeda
  • Journal Title: AIP Advances Volume: 6 Issue: 9 Pages: 095314-095314
  • DOI: 10.1063/1.4963646
  • Peer Reviewed
• [Journal Article] 鉄カルコゲナイド超伝導体の新しい電子状態相図 - 薄膜化による相分離の抑制 - (2015)
  • Author(s): 今井良宗，澤田雄一，鍋島冬樹，前田京剛
  • Journal Title: 固体物理 Volume: 50 Pages: 457-470
  • NAID: 40020568689
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] 鉄カルコゲナイド超伝導体の超伝導転移温度の大幅な上昇 (2015)
  • Author(s): 今井良宗，前田京剛
  • Journal Title: セラミックス Volume: 50 Pages: 721-721
• [Journal Article] 相分離を抑制した FeSe1-xTex薄膜の作製と超伝導転移温度の上昇 (2015)
  • Author(s): 今井良宗，澤田雄一，浅見大亮，鍋島冬樹，前田京剛
  • Journal Title: FSSTニュース Volume: 147 Pages: 7-12
  • Acknowledgement Compliant
• [Presentation] 伸張歪みを受けたFeSe薄膜の輸送特性 (2017)
  • Author(s): 川合将敬, 浅見大亮, 鍋島冬樹, 今井良宗, 前田京剛
  • Organizer: 日本物理学会第72回年次大会
  • Place of Presentation: 大阪大学豊中キャンパス（大阪府大阪市）
  • Year and Date: 2017-03-17
• [Presentation] Fe(Se,Te)薄膜の光学スペクトル (2017)
  • Author(s): 柳瀬和哉, 中島正道, 川合将敬, 浅見大亮, 鍋島冬樹, 今井良宗, 前田京剛, 宮坂茂樹, 田島節子
  • Organizer: 日本物理学会第72回年次大会
  • Place of Presentation: 大阪大学豊中キャンパス（大阪府大阪市）
  • Year and Date: 2017-03-17
• [Presentation] 梯子型鉄系化合物BaFe2X3 (X = S, Se)の磁気特性 (2017)
  • Author(s): 橋詰和樹, 今泉聖司, 五十嵐馨, 青山拓也, 今井良宗, 木村尚次郎, 大串研也
  • Organizer: 日本物理学会第72回年次大会
  • Place of Presentation: 大阪大学豊中キャンパス（大阪府大阪市）
  • Year and Date: 2017-03-17
• [Presentation] 基板材料による FeSe1-xTex の構造相転移の制御 (2017)
  • Author(s): 鍋島 冬樹、川合 将敬、浅見 大亮、今井 良宗、前田 京剛
  • Organizer: 第64回応用物理学会春季学術講演会
  • Place of Presentation: パシフィコ横浜(神奈川県横浜市)
  • Year and Date: 2017-03-14
• [Presentation] Superconductivity fluctuation of FeSe1-xTex as a function of x measured by microwave conductivity (2017)
  • Author(s): A. Maeda, F. Nabeshima, K. Nagasawa,D. Asami, M. Kawai, Y. Imai
  • Organizer: American Physical Society March Meeting 2017
  • Place of Presentation: Ernest N. Morial Convention Center, New Orleans, LA, USA
  • Year and Date: 2017-03-13
  • Int'l Joint Research
• [Presentation] Suppression of phase separation and whole phase diagram in FeSe1-xTex thin films on LaAlO3 substrates (2017)
  • Author(s): Y. Imai, F. Nabeshima, Y. Sawada, D. Asami, M. Kawai, A. Maeda
  • Organizer: American Physical Society March Meeting 2017
  • Place of Presentation: Ernest N. Morial Convention Center, New Orleans, LA, USA
  • Year and Date: 2017-03-13
  • Int'l Joint Research
• [Presentation] Critical temperature variation with a thickness tuned by electrochemical etching in FeSe1-xTex thin film on various substrates (2016)
  • Author(s): Shunsuke Kohno, Daisuke Asami, Fuyuki Nabeshima, Yoshinori Imai, Atsutaka Maeda, Kazunori Ueno
  • Organizer: 29th International Superconductivity Symposium (ISS2016)
  • Place of Presentation: 東京国際フォーラム (東京都千代田区)
  • Year and Date: 2016-12-13
  • Int'l Joint Research
• [Presentation] マイクロ波伝導度スペクトロスコピーによるFeSe薄膜の超伝導ゆらぎの研究 (2016)
  • Author(s): 長澤幸祐, 鍋島冬樹, 川合将敬, 浅見大亮, 今井良宗, 前田京剛
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学角間キャンパス（石川県金沢市）
  • Year and Date: 2016-09-13
• [Presentation] FeSe薄膜の赤外分光測定 (2016)
  • Author(s): 中島正道, 柳瀬和哉, 鍋島冬樹, 今井良宗, 前田京剛, 田島節子
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学角間キャンパス（石川県金沢市）
  • Year and Date: 2016-09-13
• [Presentation] Fe(Se,S)単結晶薄膜の育成とその輸送特性 (2016)
  • Author(s): 鍋島冬樹, 川合将敬, 浅見大亮, 今井良宗, 前田京剛
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学角間キャンパス（石川県金沢市）
  • Year and Date: 2016-09-13
• [Presentation] FeSe1-xTex薄膜の電気化学的エッチングによる超伝導転移温度制御 (2016)
  • Author(s): 河野 駿介、浅見 大亮、鍋島 冬樹、今井 良宗、前田 京剛、上野 和紀
  • Organizer: 第77回応用物理学会秋季学術講演会
  • Place of Presentation: 朱鷺メッセ(新潟県新潟市)
  • Year and Date: 2016-09-13
• [Presentation] [講演奨励賞受賞記念講演]乱れの多い鉄系超伝導体の磁束フロー (2016)
  • Author(s): 岡田 達典、鍋島 冬樹、今井 良宗、前田 京剛
  • Organizer: 第77回応用物理学会秋季学術講演会
  • Place of Presentation: 朱鷺メッセ(新潟県新潟市)
  • Year and Date: 2016-09-13
• [Presentation] 鉄系超伝導体FeSeを用いた人工超格子薄膜の作製およびその輸送特性 (2016)
  • Author(s): 浅見 大亮、鍋島 冬樹、今井 良宗、花輪 雅史、一瀬 中、塚田 一郎、前田 京剛
  • Organizer: 第77回応用物理学会秋季学術講演会
  • Place of Presentation: 朱鷺メッセ(新潟県新潟市)
  • Year and Date: 2016-09-13
• [Presentation] Suppression of phase separation and enhanced Tc in FeSe1-xTex thin films (2016)
  • Author(s): Yoshinori Imai
  • Organizer: 2016 EMN Prague Meeting
  • Place of Presentation: Grandior Prague Hotel, Prague, Czech Republic
  • Year and Date: 2016-06-21
  • Int'l Joint Research / Invited
• [Presentation] Optical study of FeSe thin film on CaF2 substrate (2016)
  • Author(s): Masamichi Nakajima, Kazuya Yanase, Fuyuki Nabeshima, Yoshinori Imai, Atsutaka Maeda, Setsuko Tajima
  • Organizer: 11th International Conference on Spectroscopies in Novel Superconductors (SNS 2016)
  • Place of Presentation: Conference Forum Schlosspark, Stuttgart/Ludwigsburg, Germany.
  • Year and Date: 2016-06-19
  • Int'l Joint Research
• [Presentation] Superconductivity fluctuation of FeSe1-xTex measured by microwave broadband technique (2016)
  • Author(s): Atsutaka Maeda, Fuyuki Nabeshima, Kosuke Nagasawa, Yoshinori Imai
  • Organizer: International Conference on Low-Energy Electrodynamics in Solids, 2016 (LEES 2016)
  • Place of Presentation: ラフォーレ琵琶湖 (滋賀県守山市)
  • Year and Date: 2016-05-29
  • Int'l Joint Research
• [Presentation] Optical spectroscopy of FeSe thin film (2016)
  • Author(s): Masamichi Nakajima, Kazuya Yanase, Fuyuki Nabeshima, Yoshinori Imai, Atsutaka Maeda, Setsuko Tajima
  • Organizer: International Conference on Low-Energy Electrodynamics in Solids, 2016 (LEES 2016)
  • Place of Presentation: ラフォーレ琵琶湖 (滋賀県守山市)
  • Year and Date: 2016-05-29
  • Int'l Joint Research
• [Presentation] Huge Superconductivity Fluctuation in Fe(Se,Te) Films (2016)
  • Author(s): Atsutaka Maeda, Yoshinori Imai, Fuyuki Nabeshima, Yuichi Sawada, Daisuke Asami, Kosuke Nagasawa
  • Organizer: 5th International Conference on Superconductivity and Magnetism (ICSM2016)
  • Place of Presentation: Fethiye, Turkey
  • Year and Date: 2016-04-24
  • Int'l Joint Research / Invited
• [Presentation] Fe(Se,Te)薄膜における超伝導ゆらぎの組成依存性 (2016)
  • Author(s): 鍋島冬樹, 長澤幸祐, 澤田雄一, 今井良宗, 前田京剛
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学泉キャンパス（宮城県仙台市）
  • Year and Date: 2016-03-20
• [Presentation] 相分離を抑制したFeSe1-xTex薄膜の強磁場下輸送特性 (2016)
  • Author(s): 今井良宗, 澤田雄一, 小濱芳允, 鍋島冬樹, 金道浩一, 前田京剛
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学泉キャンパス（宮城県仙台市）
  • Year and Date: 2016-03-20
• [Presentation] 浅見大亮, 鍋島冬樹, 澤田雄一, 今井良宗, 花輪雅史, 一瀬中, 塚田一郎, 前田京剛 (2016)
  • Author(s): FeSe/FeTe人工超格子の作製とその輸送特性
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学泉キャンパス（宮城県仙台市）
  • Year and Date: 2016-03-20
• [Presentation] Microwave Conductivity Spectroscopy for Fe(Se,Te) Thin Films (2016)
  • Author(s): F. Nabeshima, K. Nagasawa, D. Asami, Y. Sawada, Y. Imai, A. Maeda
  • Organizer: American Physical Society March Meeting 2016
  • Place of Presentation: Baltimore Convention Center, Baltimore, Maryland, USA
  • Year and Date: 2016-03-16
  • Int'l Joint Research
• [Presentation] 相分離を抑制した鉄カルコゲナイド薄膜の超伝導 (2016)
  • Author(s): 今井良宗
  • Organizer: 第57回化合物新磁性材料専門研究会「新原理・新手法による新規機能性材料の創出」
  • Place of Presentation: 東京大学浅野キャンパス 情報基盤センター（東京都文京区）
  • Invited
• [Presentation] 相分離を抑制した鉄カルコゲナイド薄膜の超伝導 (2016)
  • Author(s): 今井良宗
  • Organizer: 高温超伝導フォーラム第4回会合
  • Place of Presentation: 金沢勤労者プラザ（石川県金沢市）
  • Invited
• [Presentation] 鉄カルコゲナイド超伝導体の交流伝導度にみる超伝導ゆらぎ (2015)
  • Author(s): 前田京剛，鍋島冬樹，澤田雄一，今井良宗
  • Organizer: 第23回渦糸国内会議
  • Place of Presentation: 休暇村志賀島（福岡県福岡市）
  • Year and Date: 2015-12-08
• [Presentation] New Electronic Phase Diagram of Iron-Chalcogenide Superconductor ~ Suppression of Phase Separation using Film Fabrication ~ (2015)
  • Author(s): Yoshinori Imai
  • Organizer: 28th International Symposium on Superconductivity
  • Place of Presentation: Tower Hall Funabori, Edogawa-ku, Tokyo, Japan
  • Year and Date: 2015-11-17
  • Int'l Joint Research / Invited
• [Presentation] Fabrication and Transport Properties of FeSe/FeTe Superlattice Thin Films (2015)
  • Author(s): Fuyuki Nabeshima, Daisuke Asami, Yuichi Sawada, Yoshinori Imai, Masafumi Hanawa, Ataru Ichinose, Ichiro Tsukada, Atsutaka Maeda
  • Organizer: 28th International Symposium on Superconductivity
  • Place of Presentation: Tower Hall Funabori, Edogawa-ku, Tokyo, Japan
  • Year and Date: 2015-11-17
  • Int'l Joint Research
• [Presentation] Transport Properties of FeSe1-xTex Thin Films under Finite Magnetic Fields (2015)
  • Author(s): Yuichi Sawada, Fuyuki Nabeshima, Daisuke Asami, Ryo Ogawa, Yoshinori Imai, Atsutaka Maeda
  • Organizer: 28th International Symposium on Superconductivity
  • Place of Presentation: Tower Hall Funabori, Edogawa-ku, Tokyo, Japan
  • Year and Date: 2015-11-17
  • Int'l Joint Research
• [Presentation] 相分離を抑制したFeSe1-xTex薄膜の超伝導特性の基板依存性 (2015)
  • Author(s): 澤田雄一, 浅見大亮, 鍋島冬樹, 今井良宗, 前田京剛
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学千里山キャンパス（大阪府吹田市）
  • Year and Date: 2015-09-18
• [Presentation] 高周波測定からみたFe(Se,Te)薄膜の超伝導ゆらぎ (2015)
  • Author(s): 鍋島冬樹, 浅見大亮, 澤田雄一, 今井良宗, 前田京剛
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学千里山キャンパス（大阪府吹田市）
  • Year and Date: 2015-09-17
• [Presentation] フッ化カルシウム基板上のFeSe1-xTex膜の圧縮歪 (2015)
  • Author(s): 一瀬 中、塚田 一郎、鍋島 冬樹、今井 良宗、前田 京剛
  • Organizer: 第76回応用物理学会秋季学術講演会
  • Place of Presentation: 名古屋国際会議場（愛知県名古屋市）
  • Year and Date: 2015-09-15
• [Presentation] LaAlO3基板上に作製したFeSe1-xTex薄膜における相分離の抑制と超伝導特性 (2015)
  • Author(s): 今井 良宗、澤田 雄一、浅見 大亮、鍋島 冬樹、前田 京剛
  • Organizer: 第76回応用物理学会秋季学術講演会
  • Place of Presentation: 名古屋国際会議場（愛知県名古屋市）
  • Year and Date: 2015-09-15
• [Presentation] CaF2基板上に作製したFeSe1-xTex (x=0.15)エピタキシャル薄膜の超伝導特性 (2015)
  • Author(s): 今井 良宗、浅見 大亮、澤田 雄一、鍋島 冬樹、前田 京剛
  • Organizer: 第76回応用物理学会秋季学術講演会
  • Place of Presentation: 名古屋国際会議場（愛知県名古屋市）
  • Year and Date: 2015-09-13
• [Presentation] Suppression of Phase Separation and Enhanced Superconducting Transition Temperature of FeSe1-xTex Thin Films (2015)
  • Author(s): Yoshinori Imai, Yuichi Sawada, Fuyuki Nabeshima, Tatsunori Okada, Atsutaka Maeda
  • Organizer: 11th International Conference on Materials and Mechanisms of Superconductivity
  • Place of Presentation: Centre International de Conferences Geneve, Geneva, Switzerland
  • Year and Date: 2015-08-27
  • Int'l Joint Research
• [Presentation] 準安定相に着目して合成した超伝導体の物性 -FeSe1-xTex薄膜およびBi2Pd- (2015)
  • Author(s): 前田京剛，今井良宗，鍋島冬樹，岡田達典
  • Organizer: 基研研究会「多自由度と相関効果が生み出す超伝導の新潮流 ～BCSからBECまで～」
  • Place of Presentation: 京都大学基礎物理学研究所（京都府京都市）
  • Year and Date: 2015-06-10
  • Invited
• [Presentation] Superconductivity obtained by non-equilibrium synthesis －β-Bi2Pd and Thin films of Fe chalcogenides－ (2015)
  • Author(s): Atsutaka Maeda, Yoshinori Imai, Fuyuki Nabeshima, Tatsunori Okada, Hideyuki Takahashi, Yuichi Sawada, Ataru Ichinose, Masafumi Hanawa, Ichiro Tsukada
  • Organizer: Vortex 2015
  • Place of Presentation: El Escorial, Madrid, Spain
  • Year and Date: 2015-05-13
  • Int'l Joint Research / Invited
• [Funded Workshop] American Physical Society March Meeting 2017 (2017)
  • Place of Presentation: Ernest N. Morial Convention Center, New Orleans, LA, USA
  • Year and Date: 2017-03-13
• [Funded Workshop] 2016 EMN Prague Meeting (2016)
  • Place of Presentation: Grandior Prague Hotel, Prague, Czech Republic
  • Year and Date: 2016-06-21
• [Funded Workshop] 11th International Conference on Materials and Mechanisms of Superconductivity (2015)
  • Place of Presentation: Centre International de Conferences Geneve, Geneva, Switzerland
  • Year and Date: 2015-08-23