Collective phase oscillation in two-dimensional d-wave superconductors

Yoji Ohashi, S. Takada

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

We theoretically investigate the Carlson-Goldman (CG) mode in two-dimensional dx2-y2-wave superconductivity. In conventional s-wave superconductors, it is known that the CG mode is observed as a peak in the structure function of the pair field susceptibility S(q,ω) only just below the transition temperature Tc and only in dirty systems. On the other hand, in the d-wave state, we show that the peak structure can be observed down to T≁0.2Tc in clean systems. Furthermore, we also show that the peak splits into two when the direction of the momentum q deviates from the qx or qy axes, or nodal directions of the order parameter. These features originate from a singularity in the charge-density fluctuation due to the presence of the nodes of the d-wave order parameter: It enhances the screening of the long-range Coulomb interaction so that the CG mode can exist far below Tc. We also investigate a quasi-two-dimensional system, and show that the Josephson plasma can be observed in S(q,ω) when q is parallel to the c direction.

Original languageEnglish
Pages (from-to)5971-5983
Number of pages13
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume62
Issue number9
DOIs
Publication statusPublished - 2000 Sep 1
Externally publishedYes

Fingerprint

Superconducting materials
oscillations
Coulomb interactions
Superconductivity
Charge density
Superconducting transition temperature
Momentum
Screening
screening
superconductivity
transition temperature
magnetic permeability
momentum
Plasmas
Direction compound
interactions

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Collective phase oscillation in two-dimensional d-wave superconductors. / Ohashi, Yoji; Takada, S.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 62, No. 9, 01.09.2000, p. 5971-5983.

Research output: Contribution to journalArticle

@article{e58404ddb9f74fc6ad9c543b17fd53d8,
title = "Collective phase oscillation in two-dimensional d-wave superconductors",
abstract = "We theoretically investigate the Carlson-Goldman (CG) mode in two-dimensional dx2-y2-wave superconductivity. In conventional s-wave superconductors, it is known that the CG mode is observed as a peak in the structure function of the pair field susceptibility S(q,ω) only just below the transition temperature Tc and only in dirty systems. On the other hand, in the d-wave state, we show that the peak structure can be observed down to T≁0.2Tc in clean systems. Furthermore, we also show that the peak splits into two when the direction of the momentum q deviates from the qx or qy axes, or nodal directions of the order parameter. These features originate from a singularity in the charge-density fluctuation due to the presence of the nodes of the d-wave order parameter: It enhances the screening of the long-range Coulomb interaction so that the CG mode can exist far below Tc. We also investigate a quasi-two-dimensional system, and show that the Josephson plasma can be observed in S(q,ω) when q is parallel to the c direction.",
author = "Yoji Ohashi and S. Takada",
year = "2000",
month = "9",
day = "1",
doi = "10.1103/PhysRevB.62.5971",
language = "English",
volume = "62",
pages = "5971--5983",
journal = "Physical Review B-Condensed Matter",
issn = "1098-0121",
publisher = "American Physical Society",
number = "9",

}

TY - JOUR

T1 - Collective phase oscillation in two-dimensional d-wave superconductors

AU - Ohashi, Yoji

AU - Takada, S.

PY - 2000/9/1

Y1 - 2000/9/1

N2 - We theoretically investigate the Carlson-Goldman (CG) mode in two-dimensional dx2-y2-wave superconductivity. In conventional s-wave superconductors, it is known that the CG mode is observed as a peak in the structure function of the pair field susceptibility S(q,ω) only just below the transition temperature Tc and only in dirty systems. On the other hand, in the d-wave state, we show that the peak structure can be observed down to T≁0.2Tc in clean systems. Furthermore, we also show that the peak splits into two when the direction of the momentum q deviates from the qx or qy axes, or nodal directions of the order parameter. These features originate from a singularity in the charge-density fluctuation due to the presence of the nodes of the d-wave order parameter: It enhances the screening of the long-range Coulomb interaction so that the CG mode can exist far below Tc. We also investigate a quasi-two-dimensional system, and show that the Josephson plasma can be observed in S(q,ω) when q is parallel to the c direction.

AB - We theoretically investigate the Carlson-Goldman (CG) mode in two-dimensional dx2-y2-wave superconductivity. In conventional s-wave superconductors, it is known that the CG mode is observed as a peak in the structure function of the pair field susceptibility S(q,ω) only just below the transition temperature Tc and only in dirty systems. On the other hand, in the d-wave state, we show that the peak structure can be observed down to T≁0.2Tc in clean systems. Furthermore, we also show that the peak splits into two when the direction of the momentum q deviates from the qx or qy axes, or nodal directions of the order parameter. These features originate from a singularity in the charge-density fluctuation due to the presence of the nodes of the d-wave order parameter: It enhances the screening of the long-range Coulomb interaction so that the CG mode can exist far below Tc. We also investigate a quasi-two-dimensional system, and show that the Josephson plasma can be observed in S(q,ω) when q is parallel to the c direction.

UR - http://www.scopus.com/inward/record.url?scp=0034261429&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034261429&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.62.5971

DO - 10.1103/PhysRevB.62.5971

M3 - Article

VL - 62

SP - 5971

EP - 5983

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 1098-0121

IS - 9

ER -