TY - JOUR
T1 - Superconductivity at 40 K in the oxygen-defect perovskites la 2-xSrxCuO4-y
AU - Tarascon, J. M.
AU - Greene, L. H.
AU - Mckinnon, W. R.
AU - Hull, G. W.
AU - Geballe, T. H.
PY - 1987
Y1 - 1987
N2 - Structural, magnetic, and electronic properties of compounds in the series La//2// minus //xSr//xCuO//4// minus //y for 0. 05 less than equivalent to x less than equivalent to 1. 1, with DELTA x equals 0. 025, were studied. Resistance, susceptibility, Meissner, and shielding measurements have revealed superconductivity among several members of the series. For x equals 0. 15, the transition temperature T//C, measured at the midpoint of the resistive transition is a maximum at 39. 3 K with a width of 2 K. At other compositions the transition is broader and occurs at a lower temperature. Annealing the x equals 0. 15 sample in oxygen at 500 degree C increases T//C to 40. 3 K, while annealing at the same temperature under vacuum suppresses the superconductivity. These changes in oxygen content and T//C are reversible.
AB - Structural, magnetic, and electronic properties of compounds in the series La//2// minus //xSr//xCuO//4// minus //y for 0. 05 less than equivalent to x less than equivalent to 1. 1, with DELTA x equals 0. 025, were studied. Resistance, susceptibility, Meissner, and shielding measurements have revealed superconductivity among several members of the series. For x equals 0. 15, the transition temperature T//C, measured at the midpoint of the resistive transition is a maximum at 39. 3 K with a width of 2 K. At other compositions the transition is broader and occurs at a lower temperature. Annealing the x equals 0. 15 sample in oxygen at 500 degree C increases T//C to 40. 3 K, while annealing at the same temperature under vacuum suppresses the superconductivity. These changes in oxygen content and T//C are reversible.
UR - http://www.scopus.com/inward/record.url?scp=0023312096&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0023312096&partnerID=8YFLogxK
U2 - 10.1126/science.235.4794.1373
DO - 10.1126/science.235.4794.1373
M3 - Article
C2 - 17829979
AN - SCOPUS:0023312096
SN - 0036-8075
VL - 235
SP - 1373
EP - 1376
JO - Science
JF - Science
IS - 4794
ER -