Terahertz nonlinear optical responses in high-temperature cuprate superconductors

state, and the charge-density-wave order in copper oxide superconductors”, Physical Review B, 101, 214520, (2020).

[187] H. J. A. Molegraaf, C. Presura, D. Van der Marel, P. H. Kes, M. Li,

B. Keimer, and C. Bernhard, “Superconductivity-induced transfer of

in-plane spectral weight in Bi2 Sr2 CaCu2 O8+δ .”, Science, 295, 2239–

2241, (2002).

[188] A. B. Kuzmenko, H. J. A. Molegraaf, F. Carbone, and D. Van

der Marel, “Temperature-modulation analysis of superconductivityinduced transfer of in-plane spectral weight in Bi2 Sr2 CaCu2 O8 ”, Physical Review B, 72, 144503, (2005).

[189] R. E. Stephens and I. H. Malitson, “Index of refraction of magnesium

oxide”, Journal of Research of the National Bureau of Standards, 49,

249–252, (1952).

[190] M. Sajadi, M. Wolf, and T. Kampfrath, “Terahertz-field-induced optical birefringence in common window and substrate materials”, Optics

Express, 23, 28985, (2015).

Publication

Article

1. K. Katsumi, N. Tsuji, and Y. I. Hamada, and R. Matsunaga, J.

Schneeloch, and R. D. Zhong, and G. D. Gu, and H. Aoki, and Y.

Gallais, and R. Shimano,“Higgs mode in the d-wave superconductor

Bi2 Sr2 CaCu2 O8+x driven by an intense terahertz pulse”, Physical Review Letters 120, 117001 (2018). Editors’ suggestion.

2. H. Chu, M.-J. Kim, K. Katsumi, S. Kovalev, R. D. Dawson, L. Schwarz,

N. Yoshikawa, G. Kim, D. Putzky, Z. Z. Li, H. Raffy, S. Germanskiy,

J.-C. Deinert, N. Awari, I. Ilyakov, B. Green, M. Chen, M. Bawatna,

G. Christiani, G. Logvenov, Y. Gallais, A. V. Boris, B. Keimer, A.

Schnyder, D. Manske, M. Gensch, Z. Wang, R. Shimano and S. Kaiser,

“Phase-resolved Higgs response in superconducting cuprates”, Nature

Communications 11, 1793 (2020).

3. K. Katsumi, Z. Z. Li, H. Raffy, Y. Gallais, and R. Shimano, “Superconducting fluctuations probed by the Higgs mode in Bi2 Sr2 CaCu2 O8+x

thin films”, Physical Review B 102, 054510 (2020).

4. S. Nakamura, K. Katsumi, H. Terai and R. Shimano, “Nonreciprocal

Terahertz Second Harmonic Generation in Superconducting NbN under

Supercurrent Injection”, Physical Review Letters 125, 097004 (2020).

Review article

1. 島野亮、室谷悠太、勝見恒太、固体物理、「高強度テラヘルツ・赤外パ

ルスが拓く非平衡物性」、第 54 巻、第 11 号、623-636 (2019).

170

Publication

International Conference

1. K. Katsumi, Y. I. Hamada, R. Matsunaga, J. Schneeloch, R. D.

Zhong, G. D. Gu, Y. Gallais, and R. Shimano, “Exploring THzinduced dynamics of a d-wave superconducting condensate in the

cuprate Bi2 Sr2 CaCu2 O8+δ ” 6th International Conference on Photoinduced Phase Transitions PIPT6, Sendai, Japan, (June 4th - 9th, 2017).

2. K. Katsumi, R. Matsunaga, J. Schneeloch, R. D. Zhong, G. D. Gu, Y.

Gallais, and R. Shimano, “Terahertz pulse induced non-equilibrium dynamics of a d-wave cuprate superconductor”, International School and

Workshop on Electronic Crystals ECRYS-2017, Poster, Corse, France,

(August 21st - September 2nd, 2017).

3. K. Katsumi, N. Tsuji, and Y. I. Hamada, and R. Matsunaga, J. Schneeloch, and R. D. Zhong, and G. D. Gu, and H. Aoki, and Y. Gallais,

and R. Shimano, “Observation of Higgs mode in the d-wave superconductor Bi2 Sr2 CaCu2 O8+δ by THz pump-optical probe spectroscopy”,

Low Energy Electrodynamics of Solids LEES 2018, Poster, Portonovo,

Italy, (June 24th-29th, 2018).

4. K. Katsumi, Z. Z. Li, H. Raffy, Y. Gallais, and R. Shimano, “Observation of superconducting fluctuation in Bi2 Sr2 CaCu2 O8+x thin films by

the intense terahertz pulse-driven Higgs mode”, 2018 Workshop of Max

Planck-UBC-UTokyo Center for Quantum Materials, Poster, Hongo,

Japan, (December 9th-11th, 2018).

5. K. Katsumi, Z. Z. Li, H. Raffy, Y. Gallais, and R. Shimano, “Study

of superconducting fluctuation in cuprate superconductors through the

observation of Higgs mode oscillation”, Spectroscopies in Novel Superconductors SNS2019, Poster, Hongo, Japan, (June 16th-21th, 2019).

6. K. Katsumi, Z. Z. Li, H. Raffy, Y. Gallais, and R. Shimano, “Superconducting fluctuation probed by the terahertz pulse-driven Higgs mode

in Bi2 Sr2 CaCu2 O8+x thin films”, 2019 Workshop of Max Planck-UBCUTokyo Center for Quantum Materials, Poster, Vancouver, Canada

(December 9th-10th, 2019).

Publication

171

Domestic Conference

1. 勝見恒太、濱田裕紀、松永隆佑、Y. Gallais、島野亮、

“ Bi2 Sr2 CaCu2 O8+x

単結晶における高強度テラヘルツ波励起非平衡ダイナミクス ”、第 9 回

文部科学省「最先端の光の創成を目指したネットワーク研究拠点プロ

グラム」シンポジウム、講演番号 E-21、弘済会館, (2017 年 1 月).

2. 勝見恒太、濱田裕紀、松永隆佑、R. D. Zhong、J. Schneeloch、G. D.

Gu、Y. Gallais、島野亮、

“ 高温超伝導体 Bi2 Sr2 CaCu2 O8+x 単結晶にお

けるテラヘルツ波励起非平衡ダイナミクス ”、第 8 回低温センター研

究交流会、講演番号 P-40、東京大学、(2017 年 2 月).

3. 勝見恒太、濱田裕紀、松永隆佑、R. D. Zhong、J. Schneeloch、G. D.

Gu、Y. Gallais、島野亮、

“ Bi2 Sr2 CaCu2 O8+x 単結晶におけるテラヘル

ツ波励起非平衡ダイナミクス ”、2017 年日本物理学会第 72 回年次大会、

講演番号 18aB14-12、大阪大学、(2017 年 3 月).

4. 勝見恒太、辻直人、濱田裕紀、松永隆佑、R. D. Zhong、J. Schneeloch、

G. D. Gu、青木秀夫、Y. Gallais、島野亮、

“ Bi2 Sr2 CaCu2 O8+x 単結晶

における高強度テラヘルツ波励起非平衡ダイナミクス ”、第 10 回文部

科学省「最先端の光の創成を目指したネットワーク研究拠点プログラ

ム」シンポジウム、講演番号 E17、京都大学、(2018 年 1 月).

5. 勝見恒太、辻直人、濱田裕紀、松永隆佑、R. D. Zhong、J. Schneeloch、

G. D. Gu、青木秀夫、Y. Gallais、島野亮、

“ 高強度テラヘルツパルス

を用いた d 波超伝導体 Bi2 Sr2 CaCu2 O8+x におけるヒッグスモードの観

測”、第 9 回低温センター研究交流会、講演番号 O-04、東京大学、(2018

年 2 月).

6. 勝見恒太，R. Grasset，Y. Gallais，J. Higgins，R. Greene，島野亮、

“ Higgs spectroscopy in a d-wave superconductor ”、第 9 回低温セン

ター研究交流会、講演番号 P-42、東京大学、(2018 年 2 月).

7. 勝見恒太、Z. Z. Li、H. Raffy、Y. Gallais、島野亮、

“ 高強度テラヘル

ツ波パルス誘起ヒッグスモードを用いた Bi2 Sr2 CaCu2 O8+x 薄膜におけ

る超伝導ゆらぎの研究 ”、第 10 回低温センター研究交流会、講演番号

P-07、東京大学、(2019 年 2 月).

8. 勝見恒太、Z. Z. Li、H. Raffy、Y. Gallais、島野亮、

“ テラヘルツ波誘起

ヒッグスモードを用いた Bi2 Sr2 CaCu2 O8+x 薄膜における超伝導ゆらぎ

172

Publication

の観測”、2019 年日本物理学会第 74 回年次大会、講演番号 15aS-PS-35、

九州大学、(2019 年 3 月).

9. 中村祥子、富田圭祐、勝見恒太、寺井弘高、島野亮、

“ 電流注入下の s

波超伝導体 NbN におけるテラヘルツ第 2 高調波発生 ”、2019 年日本物

理学会第 74 回年次大会、講演番号 14pK207-10、九州大学、(2019 年 3

月).

10. 中村祥子、勝見恒太、寺井弘高、島野亮、

“ 電流注入下の s 波超伝導体

NbN におけるピン止めされた磁束に由来する偶数次高調波発生”、2019

年日本物理学会秋季大会、講演番号 12pK36-9、岐阜大学、(2019 年 9

月).

11. 勝見恒太、Z. Z. Li、H. Raffy、Y. Gallais、島野亮、

“ ヒッグスモード

を用いた銅酸化物超伝導体 Bi2 Sr2 CaCu2 O8+x における超伝導ゆらぎの

観測 ”、第 11 回低温センター研究交流会、講演番号 P-05、東京大学、

(2020 年 2 月).

12. 礒山和基、吉川尚孝、J. Wong、勝見恒太、色摩直樹、崎下雄稀、鍋島冬

樹、前田京剛、島野亮、

“ テラヘルツ波で見る鉄系超伝導体 FeSe0.5 Te0.5

の光励起状態 ”、第 11 回低温センター研究交流会、講演番号 P-06、東

京大学、(2020 年 2 月).

13. 西田森彦、勝見恒太、島野亮、光パラメトリック増幅と差周波発生を

用いた中赤外光源の開発 ”、第 11 回低温センター研究交流会、講演番

号 P-08、東京大学、(2020 年 2 月).

14. 中村祥子、勝見恒太、寺井弘高、島野亮、

“ 電流注入下の s 波超伝導体

NbN における非相反テラへルツ第 2 高調波発生 ”、第 11 回低温セン

ター研究交流会、講演番号 P-47、東京大学、(2020 年 2 月).

15. 礒山和基、吉川尚孝、J. Wong、勝見恒太、色摩直樹、崎下雄稀、鍋島

冬樹、前田京剛、島野亮、“ 光励起された鉄系超伝導体 FeSe0.5 Te0.5 か

らのテラヘルツ第 3 高調波発生 ”、 2020 年日本物理学会第 75 回年次

大会、講演番号 18p-PSB-149、名古屋大学、(2020 年 3 月).

16. 勝見恒太、西田森彦、宮坂茂樹、田島節子、島野亮、

“ 銅酸化物超伝導

体 YBa2 Cu3 Oy における光励起非平衡ダイナミクス ”、日本物理学会

2020 年秋季大会、講演番号 11aE1-4、オンライン開催、(2020 年 9 月).

Publication

173

17. 礒山和基、吉川尚孝、勝見恒太、J. Wong、色摩直樹、崎下雄稀、鍋島

冬樹、前田京剛、島野亮、

“ 鉄系超伝導体 FeSe0.5 Te0.5 における光誘起

超伝導増強、日本物理学会 2020 年秋季大会、講演番号 11aE1-3、オン

ライン開催、(2020 年 9 月).

18. 中村祥子、勝見恒太、寺井弘高、島野亮、

“ テラヘルツ第 2 高調波発生か

ら見る超伝導 NbN における磁束量子ダイナミクス、日本物理学会 2020

年秋季大会、講演番号 8aF1-4、オンライン開催、(2020 年 9 月).

Award

1. PIPT6 Best Poster Award, 6th International Conference on Photoinduced Phase Transitions PIPT6, Sendai, Japan, (June 4th - 9th, 2017).

2. 2018 Research Incentive Award (Master Course), Graduate School of

Science, The University of Tokyo, (March 22th, 2018)

3. SNS Young Researchers Award, International conference on Spectroscopies in Novel Superconductors (SNS2019), Hongo, Japan.

Acknowledgments

I would like to express my sincere gratitude to everyone who helped and

supported me during my graduate school.

First of all, I would like to thank my supervisor, Prof. Ryo Shimano,

for inspiring me to attain my research project. Also, I acknowledge his kind

advice that really helped me improve my skills in writing articles and make

presentations.

Prof. Yann Gallais at Universit´e de Paris supported me when performing

my experiments and writing articles by giving fruitful advice to interpret the

data in my master course. Even in my doctoral course, he kindly helped me

write the article. I really acknowledge his support.

I am grateful to Assistant Prof. Naotaka Yoshikawa for not only helping

me proceed with my experiments but also giving me a lot of his knowledge,

especially to handle mid-infrared pulses. The experiment with him in Dresden was one of the precious experience in my doctoral course.

I would like to thank Project Assistant Prof. Sachiko Nakamura for

telling me about the cryogenic technique and sample preparation. It was

my pleasure to work with her on the fantastic experiment of the terahertz

second-harmonic generation in NbN under current injection.

Associate Prof. Ryusuke Matsunaga at ISSP, the previous assistant professor in our group, taught me fundamental experimental skills in my master

course. I acknowledge his support and helping me improve my presentation

skills and writing applications.

I am grateful to Yuki I. Hamada for not only improving my skills for

performing experiments and analyzing data but also building the intense

terahertz pulse-generation system in my master course.

I would like to thank Associate Prof. Naoto Tsuji at Physics depertment

in University of Tokyo and Prof. Hideo Aoki at AIST for fruitful discussion and calculating the nonlinear susceptibility, which greatly helped our

176

Acknowledgments

interpretation of the Higgs mode in my master course.

I am grateful to thank Prof. Shigeki Miyasaka and Prof. Setsuko Tajima

at Osaka University for supplying us with high-quality YBCO single crystals

and giving valuable comments on my experiments.

Junior Prof. Stefan Kaiser at the Max Planck Institute for Solid State

Research in Stuttgart collaborated with us to develop the optical parametric

amplifier. I would like to appreciate his kind help. This collaboration was

achieved by the Max Planck-UBC-UTokyo center for quantum materials.

I would like to thank the sample providers, John Schneeloch, Ruidan D.

Zhong, and Genda D. Gu at Brookhaven National Lab, for supplying us with

high quality BSCCO single crystals. I would also like to thank the sample

providers, Zhi Z. Li and H´el`ene Raffy at Universit´e Paris-Saclay, for providing

us with excellent BSCCO thin films.

I also would like to thank my ALPS secondary supervisors Prof. Atushi

Fujimori and Prof. Tetsuya Hasegawa, for giving me precious comments from

different research areas.

The assistant Prof. Takenori Fujii and Dr. Ryo Toda at Cryogenic Research Center helped me use SQUID many times and polish the samples. I

would like to appreciate their support.

I want to thank all of my group members, Takuya Sawano, Hiroaki

Niwa, Yudai Iida, Kazuki Isoyama, Yoshua Hirai, Morihiko Nishida, Kunio Nishizawa, and Haruki Matsumoto, for sharing their time. I would like

to express my special gratitude to Morihiko Nishida for working with me

patiently. Also, I would like to thank Hiroaki Niwa for carefully reading this

thesis and giving feedback.

I want to thank alumni of my group, Dr. Fumiya Sekiguchi, Dr. Go Yumoto, Dr. Masayuki Takayama, Dr. Keisuke Tomita, Dr. Romain Grasset,

Kaito Tomari, Dr. Yuta Murotani, Hiroki Suganuma, and Jeremy Wong.

I would like to thank Mayuko Niwata, Eriko Sekine, and Yoko Sasaki for

helping me with endless paperwork.

Besides, I would like to appreciate the financial support from JSPS.

Finally, I would like to be grateful to my family for supporting me every

day.

...