C63uNQR Measurement of Stripe Order Parameter inLa2−xSrxCuO4

We demonstrate that one can measure the charge-stripe order parameter in the hole-doped ${\mathrm{CuO}}_2$ planes of ${\mathrm{La}}_{1.875}{\mathrm{Ba}}_{0.125}{\mathrm{CuO}}_4$, ${\mathrm{La}}_{1.48}{\mathrm{Nd}}_{0.4}{\mathrm{Sr}}_{0.12}{\mathrm{CuO}}_4$, and ${\mathrm{La}}_{1.68}{\mathrm{Eu}}_{0.2}{\mathrm{Sr}}_{0.12}{\mathrm{CuO}}_4$ utilizing the wipeout effects of ${}^{63}\mathrm{Cu}$ nuclear quadrupole resonance. Application of the same approach to ${\mathrm{La}}_{2-x}{\mathrm{Sr}}_x{\mathrm{CuO}}_4$ reveals the presence of similar stripe order for the entire underdoped superconducting regime $\frac{1}{16}\lesssim x\lesssim \frac{1}{8}$.