Point-contact spectroscopy measurements of binary superconductor MgB 2

T. Takasaki; T. Ekino; R. A. Ribeiro; T. Muranaka; H. Fujii; J. Akimitsu

doi:10.1016/j.physc.2005.01.025

Point-contact spectroscopy measurements of binary superconductor MgB ₂

T. Takasaki, T. Ekino, R. A. Ribeiro, T. Muranaka, H. Fujii, J. Akimitsu

Research output: Contribution to journal › Conference article › peer-review

5 Citations (Scopus)

Abstract

We studied the superconductor MgB₂ by point-contact spectroscopy. The first derivative conductance of the current (I)-voltage (V) characteristics dI/dV(V) displays the Andreev reflection features at the superconductor-normal metal interface. The largest gap values are estimated to be Δ(4.2 K) = 9-12 meV. We also observed clear evidences for the multiple-gaps feature with the small gap Δ(4.2 K) = 1-3 meV. These gap values agree with the previous break-junction data. The observed peak positions in the second derivative conductance (d²I/dV²(V)) are consistent with the phonon density of states of inelastic neutron scattering measurements.

Original language	English
Pages (from-to)	300-303
Number of pages	4
Journal	Physica C: Superconductivity and its applications
Volume	426-431
Issue number	I
DOIs	https://doi.org/10.1016/j.physc.2005.01.025
Publication status	Published - Oct 1 2005
Externally published	Yes
Event	Proceedings of the 17th International Symposium on Superconductivity (ISS 2004) Advances in Supeconductivity - Duration: Nov 23 2004 → Nov 25 2004

Keywords

Electron-phonon interaction
MgB
Point-contact spectroscopy
Superconducting gap

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials
Condensed Matter Physics
Energy Engineering and Power Technology
Electrical and Electronic Engineering

Access to Document

10.1016/j.physc.2005.01.025

Cite this

@article{75fd5ec385f34abe98cb38620083f2ed,

title = "Point-contact spectroscopy measurements of binary superconductor MgB 2",

abstract = "We studied the superconductor MgB2 by point-contact spectroscopy. The first derivative conductance of the current (I)-voltage (V) characteristics dI/dV(V) displays the Andreev reflection features at the superconductor-normal metal interface. The largest gap values are estimated to be Δ(4.2 K) = 9-12 meV. We also observed clear evidences for the multiple-gaps feature with the small gap Δ(4.2 K) = 1-3 meV. These gap values agree with the previous break-junction data. The observed peak positions in the second derivative conductance (d2I/dV2(V)) are consistent with the phonon density of states of inelastic neutron scattering measurements.",

keywords = "Electron-phonon interaction, MgB, Point-contact spectroscopy, Superconducting gap",

author = "T. Takasaki and T. Ekino and Ribeiro, {R. A.} and T. Muranaka and H. Fujii and J. Akimitsu",

note = "Funding Information: This work was supported in part by a Grant-in-Aid for COE research (No. 13CE2002) and for Scientific Research (No. 15540346) of the Ministry of Education, Culture, Sports, Science and Technology of Japan. We thank the Cryogenic Center, Hiroshima University for supplying liquid helium. ; Proceedings of the 17th International Symposium on Superconductivity (ISS 2004) Advances in Supeconductivity ; Conference date: 23-11-2004 Through 25-11-2004",

year = "2005",

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day = "1",

doi = "10.1016/j.physc.2005.01.025",

language = "English",

volume = "426-431",

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journal = "Physica C: Superconductivity and its Applications",

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TY - JOUR

T1 - Point-contact spectroscopy measurements of binary superconductor MgB 2

AU - Takasaki, T.

AU - Ekino, T.

AU - Ribeiro, R. A.

AU - Muranaka, T.

AU - Fujii, H.

AU - Akimitsu, J.

N1 - Funding Information: This work was supported in part by a Grant-in-Aid for COE research (No. 13CE2002) and for Scientific Research (No. 15540346) of the Ministry of Education, Culture, Sports, Science and Technology of Japan. We thank the Cryogenic Center, Hiroshima University for supplying liquid helium.

PY - 2005/10/1

Y1 - 2005/10/1

N2 - We studied the superconductor MgB2 by point-contact spectroscopy. The first derivative conductance of the current (I)-voltage (V) characteristics dI/dV(V) displays the Andreev reflection features at the superconductor-normal metal interface. The largest gap values are estimated to be Δ(4.2 K) = 9-12 meV. We also observed clear evidences for the multiple-gaps feature with the small gap Δ(4.2 K) = 1-3 meV. These gap values agree with the previous break-junction data. The observed peak positions in the second derivative conductance (d2I/dV2(V)) are consistent with the phonon density of states of inelastic neutron scattering measurements.

AB - We studied the superconductor MgB2 by point-contact spectroscopy. The first derivative conductance of the current (I)-voltage (V) characteristics dI/dV(V) displays the Andreev reflection features at the superconductor-normal metal interface. The largest gap values are estimated to be Δ(4.2 K) = 9-12 meV. We also observed clear evidences for the multiple-gaps feature with the small gap Δ(4.2 K) = 1-3 meV. These gap values agree with the previous break-junction data. The observed peak positions in the second derivative conductance (d2I/dV2(V)) are consistent with the phonon density of states of inelastic neutron scattering measurements.

KW - Electron-phonon interaction

KW - MgB

KW - Point-contact spectroscopy

KW - Superconducting gap

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DO - 10.1016/j.physc.2005.01.025

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SN - 0921-4534

VL - 426-431

SP - 300

EP - 303

JO - Physica C: Superconductivity and its Applications

JF - Physica C: Superconductivity and its Applications

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T2 - Proceedings of the 17th International Symposium on Superconductivity (ISS 2004) Advances in Supeconductivity

Y2 - 23 November 2004 through 25 November 2004

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