View in EDS

Two-gap interplay in MgB2: a tunneling spectroscopy study

Saved in:
Bibliographic Details
Title: Two-gap interplay in MgB2: a tunneling spectroscopy study
Authors: Roditchev, D.1, Giubileo, F.2 filgiu@sa.infn.it, Bobba, F.2, Lamy, R.1, Choi, E.-M.3, Kim, H.-J.3, Kang, W.N.3, Miraglia, S.4, Marcus, J.4, Sacks, W.1, Klein, J.1, Cucolo, A.M.2, Lee, S.-I.3, Fruchart, D.4
Source: Physica C. Aug2004, Vol. 408-410, p768-772. 5p.
Subjects: Superconductivity, Tunneling spectroscopy, Thin films, Temperature
Abstract: Tunneling spectroscopy on various samples of MgB2 was performed. The first direct evidence for the two-gap superconductivity was given with an inverted junction setup, in which a small crystal of MgB2 was used as the STM tip and 2H-NbSe2 as the sample. This technique allowed to show that both gaps close at the critical temperature of the bulk material and thus are intimately related to the superconductivity. The experiments performed in the standard N-I-S geometry evidenced for two strongly coupled gaps ΔL=7.0±1.0 meV and ΔS=3.0±1.0 meV at 4.2 K. STS on as-grown c-axis oriented thin films yielded only small gap which confirmed the identification of this gap as originating from 3D-like π-band and, by exclusion, that of the large gap from 2D-like σ-band. The low gap values ΔS=2.2±0.3 meV were attributed to the degraded film surface. After chemical etching, the gap increased to ΔS=2.8±0.3 meV. The c-axis tunneling spectra are better fitted considering anisotropic superconductivity inside the π-band. The issues of our findings are discussed in terms of two-band superconductivity. [Copyright &y& Elsevier]
Copyright of Physica C is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
FullText Text:
  Availability: 0
Header DbId: egs
DbLabel: Engineering Source
An: 14416503
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: Two-gap interplay in MgB<subscript>2</subscript>: a tunneling spectroscopy study
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Roditchev%2C+D%2E%22">Roditchev, D.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Giubileo%2C+F%2E%22">Giubileo, F.</searchLink><relatesTo>2</relatesTo><i> filgiu@sa.infn.it</i><br /><searchLink fieldCode="AR" term="%22Bobba%2C+F%2E%22">Bobba, F.</searchLink><relatesTo>2</relatesTo><br /><searchLink fieldCode="AR" term="%22Lamy%2C+R%2E%22">Lamy, R.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Choi%2C+E%2E-M%2E%22">Choi, E.-M.</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Kim%2C+H%2E-J%2E%22">Kim, H.-J.</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Kang%2C+W%2EN%2E%22">Kang, W.N.</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Miraglia%2C+S%2E%22">Miraglia, S.</searchLink><relatesTo>4</relatesTo><br /><searchLink fieldCode="AR" term="%22Marcus%2C+J%2E%22">Marcus, J.</searchLink><relatesTo>4</relatesTo><br /><searchLink fieldCode="AR" term="%22Sacks%2C+W%2E%22">Sacks, W.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Klein%2C+J%2E%22">Klein, J.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Cucolo%2C+A%2EM%2E%22">Cucolo, A.M.</searchLink><relatesTo>2</relatesTo><br /><searchLink fieldCode="AR" term="%22Lee%2C+S%2E-I%2E%22">Lee, S.-I.</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Fruchart%2C+D%2E%22">Fruchart, D.</searchLink><relatesTo>4</relatesTo>
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%22Physica+C%22">Physica C</searchLink>. Aug2004, Vol. 408-410, p768-772. 5p.
– Name: Subject
  Label: Subjects
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22Superconductivity%22">Superconductivity</searchLink><br /><searchLink fieldCode="DE" term="%22Tunneling+spectroscopy%22">Tunneling spectroscopy</searchLink><br /><searchLink fieldCode="DE" term="%22Thin+films%22">Thin films</searchLink><br /><searchLink fieldCode="DE" term="%22Temperature%22">Temperature</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Tunneling spectroscopy on various samples of MgB2 was performed. The first direct evidence for the two-gap superconductivity was given with an inverted junction setup, in which a small crystal of MgB2 was used as the STM tip and 2H-NbSe2 as the sample. This technique allowed to show that both gaps close at the critical temperature of the bulk material and thus are intimately related to the superconductivity. The experiments performed in the standard N-I-S geometry evidenced for two strongly coupled gaps <f>ΔL=7.0±1.0</f> meV and <f>ΔS=3.0±1.0</f> meV at 4.2 K. STS on as-grown <f>c</f>-axis oriented thin films yielded only small gap which confirmed the identification of this gap as originating from 3D-like π-band and, by exclusion, that of the large gap from 2D-like σ-band. The low gap values <f>ΔS=2.2±0.3</f> meV were attributed to the degraded film surface. After chemical etching, the gap increased to <f>ΔS=2.8±0.3</f> meV. The <f>c</f>-axis tunneling spectra are better fitted considering anisotropic superconductivity inside the π-band. The issues of our findings are discussed in terms of two-band superconductivity. [Copyright &y& Elsevier]
– Name: AbstractSuppliedCopyright
  Label:
  Group: Ab
  Data: <i>Copyright of Physica C is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.)
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=egs&AN=14416503
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1016/j.physc.2004.04.005
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 5
        StartPage: 768
    Subjects:
      – SubjectFull: Superconductivity
        Type: general
      – SubjectFull: Tunneling spectroscopy
        Type: general
      – SubjectFull: Thin films
        Type: general
      – SubjectFull: Temperature
        Type: general
    Titles:
      – TitleFull: Two-gap interplay in MgB2: a tunneling spectroscopy study
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Roditchev, D.
      – PersonEntity:
          Name:
            NameFull: Giubileo, F.
      – PersonEntity:
          Name:
            NameFull: Bobba, F.
      – PersonEntity:
          Name:
            NameFull: Lamy, R.
      – PersonEntity:
          Name:
            NameFull: Choi, E.-M.
      – PersonEntity:
          Name:
            NameFull: Kim, H.-J.
      – PersonEntity:
          Name:
            NameFull: Kang, W.N.
      – PersonEntity:
          Name:
            NameFull: Miraglia, S.
      – PersonEntity:
          Name:
            NameFull: Marcus, J.
      – PersonEntity:
          Name:
            NameFull: Sacks, W.
      – PersonEntity:
          Name:
            NameFull: Klein, J.
      – PersonEntity:
          Name:
            NameFull: Cucolo, A.M.
      – PersonEntity:
          Name:
            NameFull: Lee, S.-I.
      – PersonEntity:
          Name:
            NameFull: Fruchart, D.
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 22
              M: 08
              Text: Aug2004
              Type: published
              Y: 2004
          Identifiers:
            – Type: issn-print
              Value: 09214534
          Numbering:
            – Type: volume
              Value: 408-410
          Titles:
            – TitleFull: Physica C
              Type: main
ResultId 1