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Magnetic-field-induced charge-stripe order in the high-temperature superconductor YBa2Cu3Oy
Nuclear magnetic resonance measurements are reported showing that high magnetic fields actually induce charge order, without spin order, in the CuO2 planes of YBa2Cu3Oy, and it is argued that it is most probably the same 4a-periodic modulation as in stripe-ordered copper oxides.
Direct observation of competition between superconductivity and charge density wave order in YBa2Cu3O6.67
X-ray diffraction experiments reveal that spatial charge ordering occurs in the pseudogap state of YBa2Cu3O6.67. Moreover, this charge ordered state competes with high-temperature superconductivity,
Quantum oscillations and the Fermi surface in an underdoped high-Tc superconductor
The observation of quantum oscillations in the electrical resistance of the oxygen-ordered copper oxide YBa2Cu3O6.5 establishes the existence of a well-defined Fermi surface in the ground state of underdoped copper oxides, once superconductivity is suppressed by a magnetic field.
Change of carrier density at the pseudogap critical point of a cuprate superconductor
Measurements of the Hall coefficient in magnetic fields up to 88 tesla are used to show that Fermi-surface reconstruction by charge order in the cuprate YBa2Cu3Oy ends sharply at a critical doping p’= 0.16 that is distinctly lower than the pseudogap critical point p* =‬0.19 (ref. 11).
Evaluation of CuO 2 plane hole doping in YBa 2 Cu 3 O 6 + x single crystals
The electron hole concentration $p$ in the ${\mathrm{CuO}}_{2}$ planes of ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6+x}$ (YBCO) has been evaluated using the unit cell length in the $c$
Incipient charge order observed by NMR in the normal state of YBa2Cu3Oy
It is shown that the short-ranged charge order recently reported in the normal state of YBa2Cu3Oy corresponds to a truly static modulation of the charge density, and that this modulation impacts on most electronic properties, and it appears jointly with intra-unit-cell nematic, but not magnetic, order.
Three-dimensional charge density wave order in YBa2Cu3O6.67 at high magnetic fields
Another three-dimensionally ordered CDW emerges around the zero-field superconducting transition temperature; in contrast, the incommensurate in-plane ordering vector is field-independent, implying that the two forms of CDW and high-temperature superconductivity are intimately linked.
Emergence of charge order from the vortex state of a high-temperature superconductor.
It is shown using nuclear magnetic resonance that charge order in YBa2Cu3Oy has maximum strength inside the superconducting dome, similar to compounds of the La2-x(Sr,Ba)xCuO4 family, and that the overlap of halos of incipient charge order around vortex cores can explain the threshold magnetic field at which long-range charge order emerges.
Direct measurement of the upper critical field in cuprate superconductors
The thermal conductivity can be used to directly detect Hc2 in the cuprates Y Ba2Cu3Oy, YBa2Cu4O8 and Tl2Ba2 CuO6+δ, allowing us to map out Hc1 across the doping phase diagram, revealing that phase competition is a key limiting factor in the superconductivity of cuprates.
Electron pockets in the Fermi surface of hole-doped high-Tc superconductors
The observation of a negative Hall resistance in the magnetic-field-induced normal state of YBa2Cu3Oy and Y ba2Cu4O8, which reveals that these pockets are electron-like rather than hole-like, is reported, suggesting that a Fermi surface reconstruction also occurs in those materials, pointing to a generic property of high-transition-temperature (Tc) superconductors.