CALCIUM LADDER CUPRATE FILMS GROWN BY MOLECULAR-BEAM EPITAXY

New cuprate compounds have been synthesized by Sequentially Imposed Mo lecular Beam Epitaxy on MgO(100) substrates. The composition of the fi lms corresponds to Cah-1Cuh+1O2h with h = 3. We present X-ray diffract ion measurements performed with synchrotron radiation on a four circle s diffractometer. These films crystallize in an orthorhombic structure with a single orientation perpendicular to the substrate surface. The value of a and b parameters are in agreement with the two-leg ladder structure of the Cu2O3 planes, also observed by HREM.