https://doi.org/10.1140/epjb/e2003-00257-5
Effects of magnetic impurity Co on stripe phase of (Bi/Tl)2(Sr/Ba)2CaCu2O8+δ superconductors
1
Saha Institute of Nuclear Physics
1/AF, Bidhannagar, Calcutta 700 064, India
2
Lady Brabourne College
P1/2, Suhrawardy Avenue, Calcutta 700 017, India
Corresponding author: a poddar@cmp.saha.ernet.in
Received:
24
March
2003
Revised:
10
July
2003
Published online:
22
September
2003
The effects of Co impurity substitution at the Cu site of bilayer bismuth and thallium
cuprates have been studied over a wide range of carrier concentration.
For both the systems it is found that the suppression of the superconducting transition temperature,
Tc is more rapid
in the underdoped region. No anomalous suppression
of Tc at p ~ 1/8 (p is the hole concentration per Cu ion) is found for
different Co concentrations. This indicates that magnetic impurity Co
behaves differently with respect to pinning of dynamical stripes as
was observed in the case of non-magnetic impurity Zn by
Akoshima et al. [Phys. Rev. B 57, 7491 (1998)]
in bilayer bismuth cuprate.
Pseudogap magnitude (Eg) for each Co doping are observed to have a correspondence with a
related characteristic temperature T* obtained from thermopower measurements where
T* increases with increasing Co-concentration at a fixed carrier concentration.
Both T* and Eg are found to follow an inverse power law (~ )
with different n values.
PACS: 74.25.Fy – Transport properties (electric and thermal conductivity, thermoelectric effects, etc.) / 74.72.Hs – Bi-based cuprates / 74.72.Jt – Other cuprates, including Tl and Hg-based cuprates
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003