forgot password?
register here
Research articles
  search articles
  reviews guidelines
  articles index
My Pages
my alerts
  my messages
  my reviews
  my favorites
Members: 2191
Articles: 1'906'541
Articles rated: 2570

23 October 2019
  » arxiv » cond-mat/0406301

  Article overview

Condensation, excitation, pairing, and superfluid density in high-$T_{c}$ superconductors: magnetic resonance mode as a roton analogue and a possible spin-mediated pairing
Y.J. Uemura ;
Date 13 Jun 2004
Journal J. Phys.: Condens. Matter 16 (2004) S4515-S4540 DOI: 10.1088/0953-8984/16/40/007
Subject Superconductivity; Strongly Correlated Electrons | cond-mat.supr-con cond-mat.str-el
AbstractTo find out a primary determing factor of $T_{c}$ and a pairing mechanism in high-$T_{c}$ cuprates, we combine the muon spin relaxation results on $n_{s}/m^{*}$ (superconducting carrier density / effective mass), accumulated over the last 15 years, with the results from neutron and Raman scattering, STM, specific heat, Nernst effect and ARPES measurements. We identify the neutron magnetic resonance mode as an analogue of roton minimum in the superfluid $^{4}$He, and argue that $n_{s}/m^{*}$ and the resonance mode energy $hbaromega_{res}$ play a primary role in determining $T_{c}$ in the underdoped region. We propose a picture that roton-like excitations in the cuprates appear as a coupled mode, which has the resonance mode for spin and charge responses at different momentum transfers but the same energy transfers, as detected respectively, by the neutron S=1 mode and the Raman S=0 A1$_{g}$ mode. We shall call this as the ``hybrid spin/charge roton’’. After discussing the role of dimensionality in condensation, we propose a generic phase diagram of the cuprates with spatial phase separation in the overdoped region as a special case of the BE-BCS crossover conjecture where the superconducting coupling is lost rapidly in the overdoped region. Using a microscopic model of charge motion resonating with antiferomagnetic spin fluctuations, we propose a possibility that the hybrid spin/charge roton and higher-energy spin fluctuations mediate the superconducting pairing. In this model, the resonance modes can be viewed as a meson-analogue and the ``dome’’ shape of the phase diagram can be understood as a natural consequence of departure from the competing Mott insulator ground state via carrier doping.
Source arXiv, cond-mat/0406301
Services Forum | Review | PDF | Favorites   
Visitor rating: did you like this article? no 1   2   3   4   5   yes

No review found.
 Did you like this article?

This article or document is ...
of broad interest:
Global appreciation:

  Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.

browser CCBot/2.0 (
» my Online CV
» Free

News, job offers and information for researchers and scientists:
home  |  contact  |  terms of use  |  sitemap
Copyright © 2005-2019 - Scimetrica