Speaker
Mr
Yaroslav Kharkov
(UNSW)
Description
Discovery of charge density wave (CDW) in the pseudogap phase is
the most significant breakthrough in physics of cuprates in the past few
years. The CDW has been reported in YBCO [1,2] and
other cuprates [3,4] by several experimental groups.
Even though the microscopic mechanism of CDW and its relation to
superconductivity remains a puzzle,
it is firmly established that CDW is incommensurate with ordering wave-vector
laying in the Cu-O plane. Value of CDW wave-vector has been measured by
X-ray diffraction and by RIXS. In YBCO
CDW exist in the doping interval $0.09 \leq p \leq 0.13$ and
the wave vector, $q_{CDW}\approx (0,0,31)$ r.l.u.,
only very weakly depends on doping.
The amplitude and the pattern ("s-wave" CDW versus "d-wave" CDW)
of the CDW modulation is unknown and highly disputable
in literature. The amplitude/pattern is the very important missing piece of
information.
In the present work we point out that the most recent data on nuclear
quadrupole resonance [5]
and on phonon dispersion anomalies [6] allow to determine the amplitude and also
shed light on the pattern.
We perform the corresponding analysis of the data and for the first time
determine the amplitude of CDW.
In the proposed talk we overview CDW experiments,
explain the idea of our analysis,
and for the first time
report the value of the CDW amplitude.
[1] G. Ghiringhelli, Science {\bf 337}, 821 (2012).
[2] J. Chang, Nature Phys. \textbf{8}, 871 (2012).
[3] W. Tabis \textit{et al}, Nature Commun. \textbf{5}, 5875 (2014).
[4] R. Comin \textit{et al}, Science \textbf{343}, 390 (2014).
[5] T. Wu \textit{et al}, Nature Commun. \textbf{6}, 6438 (2015).
[6] M. Le Tacon \textit{et al}, Nature Phys. \textbf{10}, 52 (2014).
Primary author
Mr
Yaroslav Kharkov
(UNSW)
Co-author
Prof.
Oleg Sushkov
(University of New South Wales)
