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Reiss P, Graf D, Haghighirad AA, Vojta T, Coldea AI. Signatures of a Quantum Griffiths Phase Close to an Electronic Nematic Quantum Phase Transition. PHYSICAL REVIEW LETTERS 2021; 127:246402. [PMID: 34951778 DOI: 10.1103/physrevlett.127.246402] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 10/08/2021] [Indexed: 06/14/2023]
Abstract
In the vicinity of a quantum critical point, quenched disorder can lead to a quantum Griffiths phase, accompanied by an exotic power-law scaling with a continuously varying dynamical exponent that diverges in the zero-temperature limit. Here, we investigate a nematic quantum critical point in the iron-based superconductor FeSe_{0.89}S_{0.11} using applied hydrostatic pressure. We report an unusual crossing of the magnetoresistivity isotherms in the nonsuperconducting normal state that features a continuously varying dynamical exponent over a large temperature range. We interpret our results in terms of a quantum Griffiths phase caused by nematic islands that result from the local distribution of Se and S atoms. At low temperatures, the Griffiths phase is masked by the emergence of a Fermi liquid phase due to a strong nematoelastic coupling and a Lifshitz transition that changes the topology of the Fermi surface.
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Affiliation(s)
- Pascal Reiss
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - David Graf
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
| | - Amir A Haghighirad
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Thomas Vojta
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - Amalia I Coldea
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
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2
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Obata Y, Sato M, Kondo Y, Yamaguchi Y, Karateev IA, Pavlov I, Vasiliev AL, Haindl S. Chemical Composition Control at the Substrate Interface as the Key for FeSe Thin-Film Growth. ACS APPLIED MATERIALS & INTERFACES 2021; 13:53162-53170. [PMID: 34698487 DOI: 10.1021/acsami.1c14451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The strong fascination exerted by the binary compound of FeSe demands reliable engineering protocols and more effective approaches toward inducing superconductivity in FeSe thin films. Our study addresses the peculiarities in pulsed laser deposition that determine FeSe thin-film growth and focuses on the film/substrate interface, which has only been considered hypothetically in the past literature. The FeSe/MgO interface has been assumed (1) to be clean and (2) to obey lattice-matching epitaxy. Our studies reveal that both assumptions are misleading and demonstrate the tendency for domain-matching epitaxial growth, which accompanies the problem of chemical heterogeneity. We propose that homogenization of the film/substrate interface by an Fe buffer can improve the control of stoichiometry and nanostrain in a way that favors superconductivity even in ultrathin FeSe films. We will also show that on a chemically homogenized FeSe/Fe interface, the control of film texture with preparation conditions is still possible.
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Affiliation(s)
- Yukiko Obata
- Tokyo Tech World Research Hub Initiative (WRHI), Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Michiko Sato
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Yuji Kondo
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Yuta Yamaguchi
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Igor A Karateev
- National Research Centre ″Kurchatov Institute,″ pl. Akademika Kurchatova 1, Moscow 123182, Russian Federation
| | - Ivan Pavlov
- Shubnikov Institute of Crystallography of FSRC "Crystallography and Photonics" Russian Academy of Sciences, Leninsky pr. 59, Moscow 119333, Russian Federation
| | - Alexander L Vasiliev
- National Research Centre ″Kurchatov Institute,″ pl. Akademika Kurchatova 1, Moscow 123182, Russian Federation
- Shubnikov Institute of Crystallography of FSRC "Crystallography and Photonics" Russian Academy of Sciences, Leninsky pr. 59, Moscow 119333, Russian Federation
- Moscow Institute of Physics and Technology, National Research University, Dolgoprudny, Moscow region 141701, Russian Federation
| | - Silvia Haindl
- Tokyo Tech World Research Hub Initiative (WRHI), Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
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3
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Cao Z, Chen L, Cheng Z, Qiu W. Induced Superconducting Transition in Ultra-Thin Iron-Selenide Films by a Mg-Coating Process. MATERIALS (BASEL, SWITZERLAND) 2021; 14:6383. [PMID: 34771910 PMCID: PMC8585248 DOI: 10.3390/ma14216383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 11/17/2022]
Abstract
Binary Iron selenide (FeSe) thin films have been widely studied for years to unveil the high temperature superconductivity in iron-based superconductors. However, the origin of superconducting transition in this unconventional system is still under debate and worth deep investigations. In the present work, the transition from insulator to superconductor was achieved in non-superconducting FeSe ultrathin films (~8 nm) grown on calcium fluoride substrates via a simple in-situ Mg-coating by a pulsed laser deposition technique. The Mg-coated FeSe film with an optimized amount of Mg exhibited a superconducting critical temperature as 9.7 K and an upper critical field as 30.9 T. Through systematic characterizations on phase identification, carrier transport behavior and high-resolution microstructural features, the revival of superconductivity in FeSe ultrathin films is mostly attributed to the highly crystallized FeSe and extra electron doping received from external Mg-coating process. Although the top few FeSe layers are incorporated with Mg, most FeSe layers are intact and protected by a stable magnesium oxide layer. This work provides a new strategy to induce superconductivity in FeSe films with non-superconducting behavior, which might contribute to a more comprehensive understanding of iron-based superconductivity and the benefit to downstream applications such as magnetic resonance imaging, high-field magnets and electrical cables.
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Affiliation(s)
- Zhiqiang Cao
- Instrumental Analysis Center, University of Shanghai for Science and Technology, Shanghai 200093, China;
| | - Longqing Chen
- Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
| | - Zhenxiang Cheng
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong, Squires Way, North Wollongong, NSW 2500, Australia;
| | - Wenbin Qiu
- Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
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4
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Obata Y, Karateev IA, Pavlov I, Vasiliev AL, Haindl S. Challenges for Pulsed Laser Deposition of FeSe Thin Films. MICROMACHINES 2021; 12:1224. [PMID: 34683275 PMCID: PMC8540977 DOI: 10.3390/mi12101224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/28/2021] [Accepted: 10/05/2021] [Indexed: 11/16/2022]
Abstract
Anti-PbO-type FeSe shows an advantageous dependence of its superconducting properties with mechanical strain, which could be utilized as future sensor functionality. Although superconducting FeSe thin films can be grown by various methods, ultrathin films needed in potential sensor applications were only achieved on a few occasions. In pulsed laser deposition, the main challenges can be attributed to such factors as controlling film stoichiometry (i.e., volatile elements during the growth), nucleation, and bonding to the substrate (i.e., film/substrate interface control) and preventing the deterioration of superconducting properties (i.e., by surface oxidization). In the present study, we address various technical issues in thin film growth of FeSe by pulsed laser deposition, which pose constraints in engineering and reduce the application potential for FeSe thin films in sensor devices. The results indicate the need for sophisticated engineering protocols that include interface control and surface protection from chemical deterioration. This work provides important actual limitations for pulsed laser deposition (PLD) of FeSe thin films with the thicknesses below 30 nm.
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Affiliation(s)
- Yukiko Obata
- Tokyo Tech World Research Hub Initiative (WRHI), Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Igor A. Karateev
- National Research Centre “Kurchatov Institute”, pl. Akademika Kurchatova 1, 123182 Moscow, Russia;
| | - Ivan Pavlov
- Shubnikov Institute of Crystallography of FSRC “Crystallography and Photonics” Russian Academy of Sciences, Leninsky pr. 59, 119333 Moscow, Russia;
| | - Alexander L. Vasiliev
- National Research Centre “Kurchatov Institute”, pl. Akademika Kurchatova 1, 123182 Moscow, Russia;
- Shubnikov Institute of Crystallography of FSRC “Crystallography and Photonics” Russian Academy of Sciences, Leninsky pr. 59, 119333 Moscow, Russia;
- Moscow Institute of Physics and Technology, National Research University, Dolgoprudny, 141701 Moscow, Russia
| | - Silvia Haindl
- Tokyo Tech World Research Hub Initiative (WRHI), Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
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Film-thickness-driven superconductor to insulator transition in cuprate superconductors. Sci Rep 2020; 10:3236. [PMID: 32094455 PMCID: PMC7039923 DOI: 10.1038/s41598-020-60037-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 02/05/2020] [Indexed: 12/04/2022] Open
Abstract
The superconductor-insulator transition induced by film thickness control is investigated for the optimally doped cuprate superconductor La1.85Sr0.15CuO4. Epitaxial thin films are grown on an almost exactly matched substrate LaAlO3 (001). Despite the wide thickness range of 6 nm to 300 nm, all films are grown coherently without significant relaxation of the misfit strain. Electronic transport measurement exhibits systematic suppression of the superconducting phase by reducing the film thickness, thereby inducing a superconductor-insulator transition at a critical thickness of ~10 nm. The emergence of a resistance peak preceding the superconducting transition is discussed based on the weak localization. X-ray photoelectron spectroscopy results show the possibility that oxygen vacancies are present near the interface.
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6
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Current Review on Synthesis, Composites and Multifunctional Properties of Graphene. Top Curr Chem (Cham) 2019; 377:10. [DOI: 10.1007/s41061-019-0235-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 02/22/2019] [Indexed: 12/30/2022]
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Double quantum criticality in superconducting tin arrays-graphene hybrid. Nat Commun 2018; 9:2159. [PMID: 29867112 PMCID: PMC5986781 DOI: 10.1038/s41467-018-04606-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 04/24/2018] [Indexed: 11/11/2022] Open
Abstract
Two magnetic-field-induced quantum critical behaviors were recently discovered in two dimensional electron gas (2DEG) at LaTiO3/SrTiO3 interface and interpreted by disordered superconducting puddles coupled through 2DEG. In this scenario, the 2DEG is proposed to undergo a spontaneous phase separation and breaks up into locally superconducting puddles in a metallic matrix. However, as the inhomogeneous superconducting 2DEG is only illative, this proposal still lacks the direct experimental demonstration. Here, we artificially construct superconducting puddles-2DEG hybrid system by depositing tin nanoislands array on single crystalline monolayer graphene, where the two quantum critical behaviors are reproduced. Through the finite-size scaling analysis on magnetoresistivity, we show that the two quantum critical behaviors result from the intra-island and inter-island phase coherence, respectively, which are further illustrated by the phase diagram. This work provides a platform to study superconducting quantum phase transitions in a 2D system and helps to integrate superconducting devices into semiconductor technology. Two quantum critical behaviors appear in a two dimensional electron gas (2DEG) but its origin remains to be attested. Here, Sun et al. construct superconducting puddles-2DEG hybrid system by depositing tin nano-islands array on monolayer graphene where the two quantum critical behaviors are reproduced, suggesting the formation of inhomogeneous superconducting 2DEG.
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Tunable critical temperature for superconductivity in FeSe thin films by pulsed laser deposition. Sci Rep 2018; 8:4039. [PMID: 29511227 PMCID: PMC5840431 DOI: 10.1038/s41598-018-22291-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 02/19/2018] [Indexed: 12/01/2022] Open
Abstract
Stabilized FeSe thin films in ambient pressure with tunable superconducting critical temperature would be a promising candidate for superconducting electronic devices. By carefully controlling the depositions on twelve kinds of substrates using a pulsed laser deposition technique single crystalline FeSe thin films were fabricated. The high quality of the thin films was confirmed by X-ray diffraction with a full width at half maximum of 0.515° in the rocking curve and clear four-fold symmetry in φ-scan. The films have a maximum Tc ~ 15 K on the CaF2 substrate and were stable in ambient conditions air for more than half a year. Slightly tuning the stoichiometry of the FeSe targets, the superconducting critical temperature becomes adjustable below 15 K with quite narrow transition width less than 2 K. These FeSe thin films deposited on different substrates are optimized respectively. The Tc of these optimized films show a relation with the out-of-plane (c-axis) lattice parameter of the FeSe films.
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Qiu W, Ma Z, Patel D, Sang L, Cai C, Shahriar Al Hossain M, Cheng Z, Wang X, Dou SX. The Interface Structure of FeSe Thin Film on CaF 2 Substrate and its Influence on the Superconducting Performance. ACS APPLIED MATERIALS & INTERFACES 2017; 9:37446-37453. [PMID: 29019397 DOI: 10.1021/acsami.7b11853] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The investigations into the interfaces in iron selenide (FeSe) thin films on various substrates have manifested the great potential of showing high-temperature-superconductivity in this unique system. In present work, we obtain FeSe thin films with a series of thicknesses on calcium fluoride (CaF2) (100) substrates and glean the detailed information from the FeSe/CaF2 interface by using scanning transmission electron microscopy (STEM). Intriguingly, we have found the universal existence of a calcium selenide (CaSe) interlayer with a thickness of approximate 3 nm between FeSe and CaF2 in all the samples, which is irrelevant to the thickness of FeSe layers. A slight Se deficiency occurs in the FeSe layer due to the formation of CaSe interlayer. This Se deficiency is generally negligible except for the case of the ultrathin FeSe film (8 nm in thickness), in which the stoichiometric deviation from FeSe is big enough to suppress the superconductivity. Meanwhile, in the overly thick FeSe layer (160 nm in thickness), vast precipitates are found and recognized as Fe-rich phases, which brings about degradation in superconductivity. Consequently, the thickness dependence of superconducting transition temperature (Tc) of FeSe thin films is investigated and one of our atmosphere-stable FeSe thin film (127 nm) possesses the highest Tconset/Tczero as 15.1 K/13.4 K on record to date in the class of FeSe thin film with practical thickness. Our results provide a new perspective for exploring the mechanism of superconductivity in FeSe thin film via high-resolution STEM. Moreover, approaches that might improve the quality of FeSe/CaF2 interfaces are also proposed for further enhancing the superconducting performance in this system.
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Affiliation(s)
- Wenbin Qiu
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Squires Way, North Wollongong, New South Wales 2500, Australia
- Shanghai Key Laboratory of High Temperature Superconductors, Physics Department, Shanghai University , Shanghai 200444, People's Republic of China
| | - Zongqing Ma
- Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science & Engineering, Tianjin University , Tianjin 300072, People's Republic of China
| | - Dipak Patel
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Squires Way, North Wollongong, New South Wales 2500, Australia
| | - Lina Sang
- Shanghai Key Laboratory of High Temperature Superconductors, Physics Department, Shanghai University , Shanghai 200444, People's Republic of China
| | - Chuanbing Cai
- Shanghai Key Laboratory of High Temperature Superconductors, Physics Department, Shanghai University , Shanghai 200444, People's Republic of China
| | - Mohammed Shahriar Al Hossain
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Squires Way, North Wollongong, New South Wales 2500, Australia
| | - Zhenxiang Cheng
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Squires Way, North Wollongong, New South Wales 2500, Australia
| | - Xiaolin Wang
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Squires Way, North Wollongong, New South Wales 2500, Australia
| | - Shi Xue Dou
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Squires Way, North Wollongong, New South Wales 2500, Australia
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Comparative Review on Thin Film Growth of Iron-Based Superconductors. CONDENSED MATTER 2017. [DOI: 10.3390/condmat2030025] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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11
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Scaling analysis of field-tuned superconductor-insulator transition in two-dimensional tantalum thin films. Sci Rep 2017; 7:42969. [PMID: 28218296 PMCID: PMC5317156 DOI: 10.1038/srep42969] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/17/2017] [Indexed: 11/08/2022] Open
Abstract
The superconductor–insulator (SI) transition in two-dimensional Ta thin films is investigated by controlling both film thickness and magnetic field. An intriguing metallic phase appears between a superconducting and an insulating phase within a range of film thickness and magnetic field. The temperature and electric field scaling analyses are performed to investigate the nature of the SI transition in the thickness-tuned metallic and superconducting samples. The critical exponents product of νz obtained from the temperature scaling analysis is found to be approximately 0.67 in the entire range of film thickness. On the other hand, an apparent discrepancy is measured in the product of ν(z + 1) by the electric filed analysis. The product values are found to be about 1.37 for the superconducting films and about 1.86 for the metallic films respectively. We find that the discrepancy is the direct consequence of electron heating that introduces additional dissipation channels in the metallic Ta films.
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Liu X, Zhao L, He S, He J, Liu D, Mou D, Shen B, Hu Y, Huang J, Zhou XJ. Electronic structure and superconductivity of FeSe-related superconductors. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:183201. [PMID: 25879999 DOI: 10.1088/0953-8984/27/18/183201] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
FeSe superconductors and their related systems have attracted much attention in the study of iron-based superconductors owing to their simple crystal structure and peculiar electronic and physical properties. The bulk FeSe superconductor has a superconducting transition temperature (Tc) of ~8 K and it can be dramatically enhanced to 37 K at high pressure. On the other hand, its cousin system, FeTe, possesses a unique antiferromagnetic ground state but is non-superconducting. Substitution of Se with Te in the FeSe superconductor results in an enhancement of Tc up to 14.5 K and superconductivity can persist over a large composition range in the Fe(Se,Te) system. Intercalation of the FeSe superconductor leads to the discovery of the AxFe2-ySe2 (A = K, Cs and Tl) system that exhibits a Tc higher than 30 K and a unique electronic structure of the superconducting phase. A recent report of possible high temperature superconductivity in single-layer FeSe/SrTiO3 films with a Tc above 65 K has generated much excitement in the community. This pioneering work opens a door for interface superconductivity to explore for high Tc superconductors. The distinct electronic structure and superconducting gap, layer-dependent behavior and insulator-superconductor transition of the FeSe/SrTiO3 films provide critical information in understanding the superconductivity mechanism of iron-based superconductors. In this paper, we present a brief review of the investigation of the electronic structure and superconductivity of the FeSe superconductor and related systems, with a particular focus on the FeSe films.
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Affiliation(s)
- Xu Liu
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
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Schneider R, Zaitsev AG, Fuchs D, von Löhneysen H. Excess conductivity and Berezinskii-Kosterlitz-Thouless transition in superconducting FeSe thin films. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:455701. [PMID: 25319094 DOI: 10.1088/0953-8984/26/45/455701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Temperature-dependent electronic transport in the vicinity of the superconducting transition is reported for quasi-two-dimensional textured FeSe thin films. The conspicuous rounding of the resistive transitions and large transition widths are indications of excess conductivity due to thermal Cooper-pair fluctuations, which can be well-described by the two-dimensional Aslamazov-Larkin theory. The Halperin-Nelson form of the sheet resistance between the phase-ordering temperature TBKT and the mean-field temperature TMF, and the power-law behaviour of the voltage-current characteristics, with a distinctive jump of the exponent at TBKT, are indicative of a Berezinskii-Kosterlitz-Thouless transition. The complementary results suggest a two-dimensional character of superconductivity in the FeSe films and allow a quantitative estimate of the Ginzburg number Gi.
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Affiliation(s)
- R Schneider
- Institut für Festkörperphysik, Karlsruher Institut für Technologie, D-76021 Karlsruhe, Germany
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14
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Haindl S, Kidszun M, Oswald S, Hess C, Buchner B, Kolling S, Wilde L, Thersleff T, Yurchenko VV, Jourdan M, Hiramatsu H, Hosono H. Thin film growth of Fe-based superconductors: from fundamental properties to functional devices. A comparative review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2014; 77:046502. [PMID: 24695004 DOI: 10.1088/0034-4885/77/4/046502] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Fe-based superconductors bridge a gap between MgB2 and the cuprate high temperature superconductors as they exhibit multiband character and transition temperatures up to around 55 K. Investigating Fe-based superconductors thus promises answers to fundamental questions concerning the Cooper pairing mechanism, competition between magnetic and superconducting phases, and a wide variety of electronic correlation effects. The question addressed in this review is, however, is this new class of superconductors also a promising candidate for technical applications? Superconducting film-based technologies range from high-current and high-field applications for energy production and storage to sensor development for communication and security issues and have to meet relevant needs of today’s society and that of the future. In this review we will highlight and discuss selected key issues for Fe-based superconducting thin film applications. We initially focus our discussion on the understanding of physical properties and actual problems in film fabrication based on a comparison of different observations made in the last few years. Subsequently we address the potential for technological applications according to the current situation.
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15
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Chareev D, Osadchii E, Kuzmicheva T, Lin JY, Kuzmichev S, Volkova O, Vasiliev A. Single crystal growth and characterization of tetragonal FeSe1−x superconductors. CrystEngComm 2013. [DOI: 10.1039/c2ce26857d] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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