Abstract
We report a new superconductor, (Ca, A)2CuO2+yBr2-y:A=(Na, K)(Tc=24 K) with apical bromines synthesized under high pressure. X-ray powder diffraction shows that the superconducting phase has a tetragonal structure with a=3.858 Å, c=17.257 Å. This structure is so called La2CuO4 (214) type with an apical site of octahedral CuO6 being almost occupied by the bromine atoms.
