Real-space anisotropy of the superconducting gap in the charge-density wave material 2H-NbSe2

被引：27

作者：

Sanna, Antonio ^{[1
]}

Pellegrini, Camilla ^{[2
]}

Liebhaber, Eva ^{[3
]}

Rossnagel, Kai ^{[4
,5
]}

Franke, Katharina J. ^{[3
]}

Gross, E. K. U. ^{[6
]}

机构：

[1] Max Planck Inst Mikrostrukturphys, Weinberg 2, D-06120 Halle, Germany

[2] Univ Perugia, Dept Phys & Geol, Via Pascoli 33, I-06123 Perugia, Italy

[3] Free Univ Berlin, Fachbereich Phys, Arnimallee 14, D-14195 Berlin, Germany

[4] Christian Albrechts Univ Kiel, Inst Experimentelle & Angew Phys, D-24098 Kiel, Germany

[5] Deutsch Elektronen Synchrotron DESY, Ituprecht Haensellab, D-22607 Hamburg, Germany

[6] Hebrew Univ Jerusalem, Fritz Haber Ctr Mol Dynam, Inst Chem, IL-91904 Jerusalem, Israel

来源：

NPJ QUANTUM MATERIALS | 2022年 / 7卷 / 01期

基金：

欧洲研究理事会;

关键词：

ORDER; TRANSITION; EXCHANGE;

D O I：

10.1038/s41535-021-00412-8

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We present a scanning tunneling microscopy (STM) and ab-initio study of the anisotropic superconductivity of 2H-NbSe2 in the charge-density-wave (CDW) phase. Differential-conductance spectra show a clear double-peak structure, which is well reproduced by density functional theory simulations enabling full k- and real-space resolution of the superconducting gap. The hollow-centered (HC) and chalcogen-centered (CC) CDW patterns observed in the experiment are mapped onto separate van der Waals layers with different electronic properties. We identify the CC layer as the high-gap region responsible for the main STM peak. Remarkably, this region belongs to the same Fermi surface sheet that is broken by the CDW gap opening. Simulations reveal a highly anisotropic distribution of the superconducting gap within single Fermi sheets, setting aside the proposed scenario of a two-gap superconductivity. Our results point to a spatially localized competition between superconductivity and CDW involving the HC regions of the crystal.

引用

页数：7

共 70 条

[1]

ALLEN PB, 1982, SOLID STATE PHYS, V37, P1

[2] Superconductivity of MgB2: Covalent bonds driven metallic [J].

An, J.M., 2001, American Institute of Physics Inc. (86)

[3] Visualizing the charge density wave transition in 2H-NbSe2 in real space [J].

Arguello, C. J. ;

Chockalingam, S. P. ;

Rosenthal, E. P. ;

Zhao, L. ;

Gutierrez, C. ;

Kang, J. H. ;

Chung, W. C. ;

Fernandes, R. M. ;

Jia, S. ;

Millis, A. J. ;

Cava, R. J. ;

Pasupathy, A. N. .

PHYSICAL REVIEW B, 2014, 89 (23)

[4] Phonons and related crystal properties from density-functional perturbation theory [J].

Baroni, S ;

de Gironcoli, S ;

Dal Corso, A ;

Giannozzi, P .

REVIEWS OF MODERN PHYSICS, 2001, 73 (02) :515-562

[5] Interplay of charge density wave and multiband superconductivity in 2H-PdxTaSe2 [J].

Bhoi, D. ;

Khim, S. ;

Nam, W. ;

Lee, B. S. ;

Kim, Chanhee ;

Jeon, B. -G. ;

Min, B. H. ;

Park, S. ;

Kim, Kee Hoon .

SCIENTIFIC REPORTS, 2016, 6

[6] Weak Dimensionality Dependence and Dominant Role of Ionic Fluctuations in the Charge-Density-Wave Transition of NbSe2 [J].

Bianco, Raffaello ;

Monacelli, Lorenzo ;

Calandra, Matteo ;

Mauri, Francesco ;

Errea, Ion .

PHYSICAL REVIEW LETTERS, 2020, 125 (10)

[7] Heat conduction in the vortex state of NbSe2:: Evidence for multiband superconductivity -: art. no. 117003 [J].

Boaknin, E ;

Tanatar, MA ;

Paglione, J ;

Hawthorn, D ;

Ronning, F ;

Hill, RW ;

Sutherland, M ;

Taillefer, L ;

Sonier, J ;

Hayden, SM ;

Brill, JW .

PHYSICAL REVIEW LETTERS, 2003, 90 (11) :4

[8] Two Energy Gaps and Fermi-Surface "Arcs" in NbSe2 [J].

Borisenko, S. V. ;

Kordyuk, A. A. ;

Zabolotnyy, V. B. ;

Inosov, D. S. ;

Evtushinsky, D. ;

Buechner, B. ;

Yaresko, A. N. ;

Varykhalov, A. ;

Follath, R. ;

Eberhardt, W. ;

Patthey, L. ;

Berger, H. .

PHYSICAL REVIEW LETTERS, 2009, 102 (16)

[9] Effect of dimensionality on the charge-density wave in few-layer 2H-NbSe2 [J].

Calandra, Matteo ;

Mazin, I. I. ;

Mauri, Francesco .

PHYSICAL REVIEW B, 2009, 80 (24)

[10] PROPERTIES OF BOSON-EXCHANGE SUPERCONDUCTORS [J].

CARBOTTE, JP .

REVIEWS OF MODERN PHYSICS, 1990, 62 (04) :1027-1157

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