A Precise Measurement of the Oxygen Isotope Effect on the Néel Temperature in Cuprates

Figure 2

Ion current signals for the ¹⁸O₂, 18O16O, and ¹⁶O₂ molecules (red, green, and blue color, resp.) obtained during heating of the sample in a stream of helium. This graph shows that the ¹⁸O isotope fraction in the samples is bigger than 70% (see text).