Table 1. Samples used in resistance measurements.

Doping	y	Tc(0) (K)	Tc(15T) (K)	Tc(30T) (K)	Hc2 (T)
0.063	6.35	19.5	2.0	0	30±5
0.078	6.45	45.0	11.5	4.9	50±5
0.102	6.51	59.0	12.4	0	30±2
0.109	6.54	61.3	7.8	0	24±2
0.120	6.67	66.0	10.5	0	24±2
0.135	6.80	78.5	28.7	−	35±5
0.140	Y124	80.0	30.8	11.8	45±2
0.151	6.86	91.0	52.1	31.9	70±10
0.161	6.92	93.5	67.9	51.0	115±15
0.173	6.99	93.0	69.1	56.0	140±20
0.180	6.998	90.5	69.3	57.6	150±20
0.190	Ca-1.4%	87.0	65.2	53.3	140±20
0.205	Ca-5%	77.0	49.2	36.4	100±20
0.225	Tl-2201	59	—	—	63±5
0.248	Tl-2201	33	—	—	20±2
0.257	Tl-2201	20	—	—	14±2
0.260	Tl-2201	15	—	—	10±3

List of all samples whose resistivity data are used in this paper. Doping p; oxygen content y; zero-resistance T_c at H=0, H=15 T and H=30 T; upper critical field H_c2=H_vs(T=0). The H_c2 values are plotted vs p in Fig. 4a. The T_c values at H=0, 15 T and 30 T are plotted vs p in Fig. 4b. The value of H_c2=H_vs(T=0) in Tl-2201 at T_c=15 K is obtained from analysis of published data (see Supplementary Figs 3 and 4).