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ARPES Studies of 1111-type Fe-pnictide high-temperature superconductors

English title ARPES Studies of 1111-type Fe-pnictide high-temperature superconductors
Applicant Shi Ming
Number 137783
Funding scheme Project funding (Div. I-III)
Research institution Paul Scherrer Institut
Institution of higher education Paul Scherrer Institute - PSI
Main discipline Condensed Matter Physics
Start/End 01.09.2012 - 31.08.2015
Approved amount 189'329.00
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Keywords (5)

high-temperature superconductivity; angle-resolved photoemission (ARPES); electronic structure; condensed matter physics; iron pnictide

Lay Summary (English)

Lead
Lay summary

The superconducting state is a special phase of matter with the features of vanishing electric resistivity and the expulsion of external magnetic flux. Uncovering the mechanism of the high-temperature superconductivity in complex materials, such as iron- and copper-based superconducting compounds, has essential importance in their potential industrial applications, e.g. building power-distribution cables and powerful motors. The aim of this project is to study the electronic structure and the low-energy electronic excitations of 1111 iron-pnictides, which have the highest superconducting transition temperature among the newly discovered iron-based superconductors. This will advance our understanding of various exotic properties of this class of materials and shed light on the microscopic origin of the high-temperature superconductivity in iron-pnictides.

Because the physical properties in solids are govern by the interactions between multiple degrees of freedom, an essential piece of knowledge is how the electronic states and excitation spectra change from one phase to another. In this project we shall concentrate our studies on the electronic structure and charge excitations of iron-pnictides. By using high-resolution angle-resolved photoemission spectroscopy (ARPES) and soft X-ray ARPES stations at Swiss Light Source (SLS), we will investigate how the electronic structure evolves under the structural transition from a tetragonal structure to an orthorhombic one, and under phase transitions from an antiferromagnetically ordered phase (AFM) to a superconducting state, and from a normal state to a superconducting state. We shall also investigate the relation between the superconducting phase and other instabilities in this class of materials. These studies will provide essential ingredients for uncovering the mechanism for the emergence of the high-temperature superconductivity in this class of materials.
Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Employees

Publications

Publication
Internal pressure in superconducting Cu intercalated Bi2Se3
Ribak Amit, Chashka Khanan B., Lahoud Elias, Naamneh Muntaser, Rinott Shahar, Ein-Eli Yair, Plumb Nicholas C., Shi Ming, Rienks Emile, Kanigel Amit (2016), Internal pressure in superconducting Cu intercalated Bi2Se3, in Phys. Rev. B, 93, 064505.
Observation of Dirac-like band dispersion in LaAgSb2
Shi Xun, RichardP., Wang Kefeng, Liu M., Matt C. E., Xu Nan, DhakaR. S., Ristic Z., Qian T., Yang Y. -F., Petrovic C., Shi Ming, Ding Hong (2016), Observation of Dirac-like band dispersion in LaAgSb2, in Phys. Rev. B, 93, 081105.
Observation of Weyl nodes and Fermi arcs in tantalum phosphide
Xu Nan, Weng H. M., Lv B. Q., Matt C. E., Park J., Bisti F., Strocov V. N., Gawryluk D., Pomjakushina E., Conder K., Plumb N. C., Radovic M., Autes G., Yazyev O. V., Fang Z., Dai X., Qian T., Mesot J., Ding H., Shi Ming (2016), Observation of Weyl nodes and Fermi arcs in tantalum phosphide, in Nature Communications, 7, 11006.
Camelback-shaped band reconciles heavy-electron behavior with weak electronic Coulomb correlations in superconducting TiNi2Se2
Xu Nan, Matt Christian Egon, Richard Pierre, Roekeghem A. van, Biermann S., Shi Xun, Wu S. -F, Liu H. W., Chen D., Qian Tian, Plumb Nicholas Clark, Radovic Milan, Wang Hangdong, Mao Qianhui, Du Jianhua, Fang Minghu, Mesot Joel, Ding. Hong, Shi Ming (2015), Camelback-shaped band reconciles heavy-electron behavior with weak electronic Coulomb correlations in superconducting TiNi2Se2, in Phys. Rev. B, 92, 081116.
Electron scattering, charge order, and pseudogap physics in La1.6-xNd0.4SrxCuO4: An angle-resolved photoemission spectroscopy study
Matt Christian Egon, Fatuzzo C. G., Sassa Y., Mansson Martin, Fatale S., Bitetta V., Shi Xun, Pailhes S., Berntsen M. H., Kurosawa T., Oda M, Momono N., Lipscombe O. J., Hayden S. M., Yan J. -Q., Zhou J. -S., Goodenough J. B., Pyon S., Takauama T., Takagi H., Patthey Luc, Bendounan A., Razzoli Elia, Shi Ming, Plumb Nicholas Clark (2015), Electron scattering, charge order, and pseudogap physics in La1.6-xNd0.4SrxCuO4: An angle-resolved photoemission spectroscopy study, in Phys. Rev. B, 92, 134524.
High-temperature superconductivity from fine-tuning of Fermi-surface singularities in iron oxypnictides
Charnukha A., Evtushinsky D. V., Matt Christian Egon, Xu N., Shi Ming, Buchner B., Zhigadlo N. D., Batlogg B., Borisenko S. V. (2015), High-temperature superconductivity from fine-tuning of Fermi-surface singularities in iron oxypnictides, in Scientific Reports, 5, 18273.
Observation of Fermi-Arc Spin Texture in TaAs
Lv B. Q., Muff S., Qian T., Song Z. D., Nie S. M., Xu Nan, Richard P., Matt Christian Egon, Plumb N. C., Zhao L. X., Chen G. F., Fang Z., Dai X., Dil J. H., Mesot J., Shi Ming, Weng H. M., Ding H. (2015), Observation of Fermi-Arc Spin Texture in TaAs, in Phys. Rev. Lett., 115, 217601.
Observation of Weyl nodes in TaAs
Lv Baiqing, Xu Nan, Weng Hongming, Ma Junzhang, Richard Pierre, Zhao L. X., Chen G. -F., Matt Christian Egon, Bisti F., Strocov V. N., Mesot Joel, Fang Zhong, Dai Xi, Qian Tian, Shi Ming, Ding Hong (2015), Observation of Weyl nodes in TaAs, in Nature Physics, 11, 724.
Tuning electronic correlations in transition metal pnictides: Chemistry beyond the valence count
Razzoli Elia, Matt Christian Egon, Kobayashi M., Wang Xiaoping, Strocov V. N., Roekeghem A. van, Biermann S., Plumb Nicholas Clark, Radovic Milan, Schmitt Thorsten, Capan C., Fisk Z., Richard Pierre, Ding Hong, Aebi Philipp, Mesot Joel, Shi Ming (2015), Tuning electronic correlations in transition metal pnictides: Chemistry beyond the valence count, in Phys. Rev. B, 91, 214502.
Direct observation of the spin texture in SmB6 as evidence of the topological Kondo insulator
Xu Nan, Biswas Pabitra Kumar, Dil Jan Hugo, Dhaka R. S., Landolt Gabriel, Muff Stefan, Matt Christian Egon, Shi Xun, Plumb Nicholas Clark, Radovic Milan, Pomjakushina Ekaterina, Conder Kazimierz, Amato Alex, Borisenko S. V., Yu R, Weng H. -M, Fang Zhong, Dai Xi, Mesot Joel, Ding Hong, Shi Ming (2014), Direct observation of the spin texture in SmB6 as evidence of the topological Kondo insulator, in Nature Communications, 5, 4566.
Exotic Kondo crossover in a wide temperature region in the topological Kondo insulator SmB6 revealed by high-resolution ARPES
Xu Nan, Matt Christian Egon, Pomjakushina Ekaterina, Shi Xun, Dhaka R. S., Plumb Nicholas Clark, Radovic Milan, Biswas Pabitra Kumar, Evtushinsky D., Zabolotnyy V., Dil Jan Hugo, Conder Kazimierz, Mesot Joel, Ding Hong, Shi Ming (2014), Exotic Kondo crossover in a wide temperature region in the topological Kondo insulator SmB6 revealed by high-resolution ARPES, in Phys. Rev. B, 90, 085148.
Possible nodal superconducting gap and Lifshitz transition in heavily hole-doped Ba0.1K0.9Fe2As2
Xu Nan, Richard Pierre, Shi Xun, Roekeghem. A. van, Qian Tian, Razzoli Elia, Rienks E., Chen G. -F., Ieki E., Nakayama K., Sato T., Takahashi T., Shi Ming, Ding Hong (2013), Possible nodal superconducting gap and Lifshitz transition in heavily hole-doped Ba0.1K0.9Fe2As2, in Phys. Rev. B, 88, 220508.
Surface and bulk electronic structure of the strongly correlated system SmB6 and implications for a topological Kondo insulator
Xu Nan, Shi Ming (2013), Surface and bulk electronic structure of the strongly correlated system SmB6 and implications for a topological Kondo insulator, in PHYSICAL REVIEW B, 88, 121102.
A resonant inelastic x-ray scattering study of the spin and charge excitations in the overdoped superconductor La1.77Sr0.23CuO4
Monney M., Schmitt T., Matt Christian Egon, Mesot Joel, Strocov V. N., Lipscombe O. J., Hayden S. M., Chang J., A resonant inelastic x-ray scattering study of the spin and charge excitations in the overdoped superconductor La1.77Sr0.23CuO4, in Phys. Rev. B.

Collaboration

Group / person Country
Types of collaboration
Prof. H. Ding, Institute of Physics, CAS China (Asia)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Dr. J. Karpinski, ETHZ Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Prof. Dr. J. Mesot, EPFL+PSI Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Prof. J. C. Campuzano, Univ. of Illinois at Chicago United States of America (North America)
- Industry/business/other use-inspired collaboration
Dr. J. Minár, Universität München Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Dr. B. Delley, PSI Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Dr. M. R. Norman, Argonne National Lab. United States of America (North America)
- Industry/business/other use-inspired collaboration
MaNEP Switzerland (Europe)
- Exchange of personnel

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
Joint Annual Meeting of ÖPG, SPG, ÖGAA und SGAA Talk given at a conference The effect of As-chain layers on the electronic structure in ‘112’ iron-pnictides – a high-resolution ARPES study 01.09.2015 Vienna, Austria Matt Christian Egon;
International conference M2S HTSC 2015 Poster The effect of As-chain layers on the electronic structure in ‘112’ iron-pnictides – a high-resolution ARPES study 23.08.2015 Geneva, Switzerland Matt Christian Egon;
International conference M2S HTSC 2015 Talk given at a conference Camelback-shaped band reconciles heavy electron behavior with weak electronic Coulomb correlations in superconducting TlNi2Se2 23.08.2015 Geneva, Switzerland Matt Christian Egon;
Superstripes 2015 Talk given at a conference Tuning electronic correlations in transition metal pnictides: chemistry beyond the valence count 13.06.2015 Ischia, Italy Shi Ming;
Gordon Research Conference: Unconventional Superconductivity: Materials and Mechanism Poster The effect of As-chain layers on the electronic structure in ‘112’ iron-pnictides – a high-resolution ARPES study 23.05.2015 Chinese University of Hong Kong, Hong Kong, China Matt Christian Egon;
SMEC 2015 conference Talk given at a conference Tuning electronic correlations in transition metal pnictides: chemistry beyond the valence count 08.03.2015 Miami, United States of America Shi Ming;
27th International Conference on Low Temperature Physics Talk given at a conference Spin- and angle-resolved photoemission on the first topological Kondo insulator: SmB6 06.08.2014 Buenos Aires, Argentina Shi Ming;
Superstripes 2014 Talk given at a conference Rotation symmetry breaking in La2-xSrxCuO4 revealed by ARPES 25.07.2014 Erice, Italy Shi Ming;
SPS Annual Meeting 2014 Talk given at a conference Disentanglement of pseudogap and charge stripe 30.06.2014 Fribourg, Switzerland Matt Christian Egon;
The 12th Beijing forum on high-temperature superconductivity Talk given at a conference Electron-electron correlation in iron-pnictide superconductors 24.05.2014 Luoyang, China Shi Ming;
The 4th PSI - IOP joint workshop Talk given at a conference Bandwidth renormalization in 122 iron pnictides studies by soft X-ray ARPES 16.10.2013 Beijing, China Matt Christian Egon;
SMEC 2013 conference Talk given at a conference Superconductivity 23.03.2013 Miami, United States of America Shi Ming;


Associated projects

Number Title Start Funding scheme
159678 ARPES studies of iron-pnictide and BKBO superconductors 01.05.2016 Project funding (Div. I-III)

Abstract

The aim of this project is to study the electronic structure and the low-energy electronic excitations of 1111 iron-pnictides (Fe-pnictides), which have the highest superconducting transition temperature (Tc) among the newly discovered iron-based superconductors. This will advance our understanding of various exotic properties of this class of materials and shed light on the microscopic origin of the high-temperature superconductivity in Fe-pnictides.Since the discovery of superconductivity in F-doped LaFeAsO with Tc = 26 K in early 2008, significant attention has been paid to ZrCuSiAs-type compounds. Further studies on RFeAsO1-xFx (R, rare-earth metal) have shown that Tc is extremely sensitive to the lanthanide, exceeding 50 K for the Nd- and Sm-containing oxypnictides. The experimental evidence accumulated so far has shown that intriguing couplings between superconductivity, magnetism, and structural features are present. The magnetic phase appears to be associated with a distortion of the crystal lattice from a tetragonal to an orthorhombic structure. In some materials the antiferromagnetic order persists into the superconducting phase (e.g. SmOFeAs). In other cases the antiferromagnetic and superconducting phases are completely separated. Increasing fluorine content suppresses both the magnetic order and the structural distortion, and the superconductivity emerges.Because many physical properties in solids are governed by the electronic states, an essential piece of knowledge is how the electronic structure and excitation spectra change from one phase to another. A systematic study of the momentum-resolved electronic structure of RFeAsO1-xFx as a function of doping and temperature is still lacking in the current literature. One of the main reasons is lack of high quality large-size single-crystal samples in 1111 systems for the spectroscopic techniques that probe the charge excitation spectra of single-particle spectral function. In collaboration with Dr. J. Karpinski’s group at ETHZ, we successfully made preliminary angle-resolved photoemission (ARPES) measurements on the newly grown NdFeAsO1-xFx samples. This progress opens the door for us to explore the electron excitations in the momentum-resolved manner for the important 1111 systems of Fe-based superconductors.In the proposed project we shall concentrate our studies on two 1111 families NdFeAsO1-xFx and SmFeAsO1-xFx. Although both systems have Tc beyond 50 K, their temperature-doping phase diagrams are apparently different (Fig. 1). By using high-resolution ARPES and soft X-ray ARPES stations at Swiss Light Source (SLS), we will investigate how the electronic structure evolves under the structural transition from a tetragonal structure to an orthorhombic one, and under phase transitions from an antiferromagnetically ordered phase (AFM) to a superconducting state, and from a normal state to a superconducting state. We shall investigate whether there is a connection between Fermi surface nesting and a spin-density-wave (SDW) instability that has been proposed to account for the small Fe moments in rare-earth oxypnictides, and how the different Fe moments are related to the difference in band structures of different materials. Along with studies of electron correlation effects, we shall measure the superconducting gap and its momentum-dependence as function of F-doping and temperature. Knowledge of the electron pairing strength and the shape in momentum-space of the superconducting order parameters will provide essential ingredients for uncovering the pairing mechanism for the emergence of the high-temperature superconductivity.
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