Charge density waves and Fermi surface reconstruction in the clean overdoped cuprate superconductor Tl2Ba2CuO6+δ

The origin of the Fermi surface reconstruction that occurs in cuprate superconductors as hole doping increases remains unclear. Here, the authors observe long range charge density wave (CDW) order in the overdoped single-layer cuprate Tl2Ba2CuO6+delta, which then disappears above a hole concentration 0.265, suggesting a correlation between Fermi surface reconstruction and the emergence of the CDW. Hall effect and quantum oscillation measurements on high temperature cuprate superconductors show that underdoped compositions have small Fermi surface pockets whereas when heavily overdoped, a single much larger pocket is found. The origin of this change in electronic structure has been unclear, but may be related to the high temperature superconductivity. Here we show that the clean overdoped single-layer cuprate Tl2Ba2CuO6+delta (Tl2201) displays CDW order with a remarkably long correlation length xi approximate to 200 angstrom which disappears above a hole doping of p(CDW) approximate to 0.265. We show that the evolution of the electronic properties of Tl2201 as the doping is lowered may be explained by a Fermi surface reconstruction which accompanies the emergence of the CDW below p(CDW). Our results demonstrate importance of CDW correlations in understanding the electronic properties of overdoped cuprates.

Automated summary

The authors observed long range CDW order in Tl2Ba2CuO6+delta, which disappears above a certain hole doping concentration, suggesting a correlation with Fermi surface reconstruction. The evolution of electronic properties in Tl2201 may be explained by a Fermi surface reconstruction accompanying the emergence of CDW. This highlights the importance of CDW correlations in understanding overdoped cuprates.