主要研究方向
本課題組研究方向可概括為“基於高通量組合薄膜技術探索新(超導)材料及物理研究”。
1.尋找新的(超導)材料。以先進的高通量合成技術為主要手段,製備外延組合薄膜及界面。超導薄膜通常是在超導多晶材料報導後才陸續被製備出來,但通過組合製備方法可以在同一塊襯底上製備出連續組分且空間可分辨的高質量外延薄膜。高通量組合製備及微區高速表征技術是材料基因計畫(Materials Genome Initiative)的核心技術,可加速材料研發周期,保障新(超導)材料探索的可執行性。此外製備異質結/超晶格,利用界面發現新超導材料或者提高超導轉變溫度亦是我們感興趣的研究內容。
2.探索高溫超導機理。選取對機理理解至關重要卻缺乏高質量單晶塊體的氧化物體系,製備出高質量的(亞穩態)單晶薄膜。工作圍繞高溫超導體系中與機理密切相關的量子臨界效應來展開,包括組分摻雜、強磁場、靜電場等多種調控手段。發揮組合外延薄膜的優勢深入挖掘高溫超導體系的多維電子態相圖,揭示其豐富的物理內容。
過去的主要工作及獲得的成果
1.在高溫超導體機理研究方面,a)國際上第一次從實驗上給出了電子型銅氧化物過摻雜區域完整的相圖(測量至20mK),該相圖已被著名理論學家D.Scalapino在2012年為Rev. Mod. Phys.上撰寫的綜述所採用。b)首次發現電子型銅氧化物中超導電性和線性電阻(高溫超導領域中常提到的“strange metal”)的散射率的強度密切相關。c)首次揭示電子型銅氧化物體系和超導邊界有關的第二種量子漲落。相關結果以第一作者發布在Nature(2011)和PNAS(2012)上,並在2012美國APS March Meeting邀請專場做邀請報告。
2.製備高質量的唯一尖晶石氧化物超導單晶薄膜,結合電輸運和點接觸隧道譜首次獲得該體系的電子態相圖,發現隨溫度升高其超導態上方存在軌道相關序,繼續升溫進入自旋漲落區域(詳細請點擊)。部分結果發表在Nature Commun.(2015)。
3.在探索新超導體方面,通過高通量組合薄膜技術發現了一種新的超導材料,是該技術迄今所發現的第一個新超導材料,部分結果發布在APL Mater.(2013)上。在建設與發展高通量組合薄膜生長和微區測量設備方面,自2013年已申請相關發明專利逾10項。
代表性論文及專利
[20] G. He, Y.L. Jia, X.Y. Hou, Z.X. Wei, H.D. Xie, Z.Z. Yang, J. Yuan, L. Shan, B.Y. Zhu, H. Li, L. Gu, K. Liu, T. Xiang and K. Jin,Observation of anisotropic electronic correlations in the spinel oxide superconductor
[19] M. C. Wang, H. S. Yu, Y. -F. Yang, S. N. Luo, K. Jin, and J. Qi, Interplay between 2D antiferromagnetic correlations and superconductivity in oxygen-tuned La2-xCexCuO4±δ revealed by ultrafast optical spectroscopy
[18] H.S. Yu, G. He, Z.Q. Lin, J. Yuan, B.Y. Zhu, Y.F. Yang, T. Xiang, F.V. Kusmartsev, L. Li, J.F. Wang, and K. Jin, A close look at antiferromagnetism in multidimensional phase diagram of electron-doped copper oxide
[17] D.N. Yuan, J. Yuan, Y.L. Huang, S.L. Ni, Z.P. Feng, H.X. Zhou, K. Jin, G.M. Zhang, X.L. Dong, F. Zhou, and Z.X. Zhao, Observation of Ising spin-nematic order and its close relationship to the superconductivity in FeSe single crystals, Phys. Rev
[16] X. Zhang, H.S. Yu, G. He, W. Hu, J. Yuan, B.Y. Zhu, and K. Jin, Transport anomalies and quantum criticality in electron-doped cuprate superconductors,
[15] K. Jin, W. Hu, B.Y. Zhu, D. Kim, J. Yuan, Y.J. Sun, T. Xiang, M.S. Fuhrer, I. Takeuchi, and R.L. Greene, Evolution of electronic states in n-type copper oxide superconductor via electric double layer gating, Sci
[14] J. Yuan, G. He, H. Yang, Y. Shi, B.Y.Zhu and K. Jin, Research trends in electron-doped cuprate superconductors, Sci. China-Phys. Mech. Astron
[13] X. Dong, K. Jin, D.N. Yuan, H.X. Zhou, J. Yuan, Y.L. Huang, W. Hua, J.L. Sun, P. Zheng, W. Hu, Y.Y. Mao, M.W. Ma, G.M. Zhang, F. Zhou, and Z.X. Zhao, (Li0.84Fe0.16)OHFe0.98Se superconductor: Ion-exchange synthesis of large single crystal and anomalous normal state properties, Phys. Rev
[12] K. Jin, G. He, X. Zhang, S. Maruyama, S. Yasui, R. Suchoski, J. Shin,Y. Jiang, H.S. Yu, J. Yuan, L. Shan, F.V. Kusmartsev, R. L. Greene, and I.Takeuchi, Anomalous magnetoresistance in the spinel superconductor LiTi2O4, Nature Commun
[11] X. Dong, H.X. Zhou, H.X. Yang, J. Yuan, K. Jin, F. Zhou, D.N. Yuan, L.L. Wei, J.Q. Li, X.Q. Wang, G.M. Zhang, and Z.X. Zhao, Phase diagram of (Li1-xFex)OHFeSe: a bridge between iron selenide and arsenide superconductors, J. Am. Chem
[10] H. Saadaoui, Z. Salman, H. Luetkens, T. Prokscha, A. Suter, W.A. MacFarlane, Y. Jiang, K. Jin, R.L. Greene, E. Morenzoni, and R.F. Kiefl, The phase diagram of electron-doped La2-xCexCuO4-δ, Nature Commun
[9] K. Jin, R. Suchoski, S. Fackler, Y. Zhang, X. Pan, R. L. Greene, and I. Takeuchi, Combinatorial search of superconductivity in Fe-B composition spreads, APL Mater
[8] N. P. Butch*, K. Jin*, K. Kirshenbaum, R. L. Greene, and J. Paglione, Quantum critical scaling at the edge of Fermi liquid stability in a cuprate superconductor, Proc. Natl. Acad
[7] K. Jin, N. P. Butch, K. Kirshenbaum, J. Paglione, and R. L. Greene, Link between spin fluctuations and electron pairing in copper oxide superconductors, Nature
[6] K. Jin, P. Bach, X. H. Zhang, U. Grupel, E. Zohar, I. Diamant, Y. Dagan, S. Smadici, P. Abbamonte, and R. L. Greene, Anomalous enhancement of the superconducting transition temperature of electron-doped La2-xCexCuO4 and Pr2-xCexCuO4 cuprate heterostructures, Phys
[5] K. Jin, X.H. Zhang, P. Bach, and R.L. Greene, Evidence for antiferromagnetic order in La2-xCexCuO4 from angular magnetoresistance measurements, Phys
[4] K. Jin, B. Y. Zhu, B. X. Wu, L. J .Gao, and B. R. Zhao, Low temperature Hall effect in electron-doped superconductor La2-xCexCuO4 thin films, Phys
[3] K. Jin, B. Y. Zhu, B. X. Wu, J. Vanacken, V. V. Moschalkov, B. Xu, L. X. Cao, X. G. Qiu, and B. R. Zhao, Normal-state transport in electron-doped La2-xCexCuO4 thin films in magnetic fields up to 40 Tesla, Phys. Rev
[2] K. Jin, B. Y. Zhu, J. Yuan, H. Wu, L. Zhao, B. X. Wu, Y. Han, B. Xu, L. X. Cao, X. G. Qiu, and B. R. Zhao, Evolution of Charge Carriers for transport in electron-doped cuprate superconductor La1.89Ce0.11CuO4 thin films, Phys
[1] K. Jin, J. Yuan, L. Zhao, H. Wu, X. Y. Qi, B. Y. Zhu, L. X. Cao, X. G. Qiu, B. Xu, X. F. Duan, and B. R. Zhao, Coexistence of superconductivity and ferromagnetism in a dilute cobalt-doped La1.89Ce0.11CuO4±δ system, Phys. Rev
目前的研究課題及展望
1.電子型高溫超導銅氧化物體系。包括量子臨界點的確認和調控,測量包括電磁、熱及點接觸隧道譜等,最終建立以鈰、氧為化學參量,含溫度、磁場等變數的高維相圖。通過與空穴型體系的對比,理解銅氧化物的超導機制。
2.其它氧化物超導體系薄膜的製備及物理研究,如唯一尖晶石結構氧化物超導體等。
3.自主設計各類微區快速表征系統以及原位表征系統,適應高通量材料的表征需求。套用高通量組合薄膜製備與快速表征技術探索新(超導)材料。
4.尋找新的界面超導體系。以超薄膜或各類有序量對界面的調製為突破口,獲取更高的超導轉變溫度。