Robust CDW

Our latest work on the cuprate charge dnsity wave (CDW) has been published in Physical Review letters.

Robust Charge Density Wave Correlations in Optimally Doped YBa2⁢Cu3⁢Oy R. Zhou et al. Phys. Rev. Lett. 135, 106503 – Published 3 September, 2025

Charge density wave (CDW) order is a key property of high-𝑇𝑐 cuprates, but its boundaries in the phase diagram and potential connections to other phases remain controversial. We report nuclear magnetic resonance (NMR) measurements in the prototypical cuprate YBa2⁢Cu3⁢Oy demonstrating that short-range static CDW order remains robust at optimal doping (𝑝 =0.165), exhibiting a strength and temperature dependence in the normal state similar to those observed at 𝑝 ≃0.11 in the underdoped regime. For an overdoped sample with 𝑝 =0.184, we detect no static CDW down to 𝑇 =𝑇𝑐, though weak CDW order plausibly emerges below 𝑇𝑐. More broadly, we argue that both quenched disorder and competition with superconductivity influence the apparent boundary of the CDW phase, likely causing an underestimation of its intrinsic extent in doping. These findings challenge the view that the CDW phase boundary lies below 𝑝* ≃0.19, widely regarded as the critical doping where the pseudogap phase ends in YBa2⁢Cu3⁢Oy.