Fig. 1

Field and temperature evolution of NMR satellite line for underdoped Bi2201. a–d The NMR satellite (3/2 ↔ 1/2 transition) lines for Bi₂Sr_2−x La _x CuO_6+δ with x = 0.4 (p = 0.162), x = 0.6 (p = 0.135), x = 0.65 (p = 0.128), and x = 0.75 (p = 0.114). The curves for p = 0.135, 0.128, and 0.114 at T = 4.2 K are the sum of two Gaussian functions (shaded area). f _peak is the peak frequency. The intensity is normalized by the area of the spectrum. e Field evolution of the line splitting δf for p = 0.114 at T = 4.2 K. f Temperature evolution of δf for p = 0.114 under various fields. The solid arrows indicate T _CDW. The dotted arrows indicate T _c(H). Error bars represent the uncertainty in estimating δf