Crystal growth and twins in La((1-x))SrxMnO3

We present crystal growth experiments of the colossal magneto resistance ma terial La(1-x)SrxMnO3 using a CO2-laser heated floating zone method. Invest igations of the solidified molten zone show that La2O3 and MnO is formed in the melt using atmospheres with an O-2 pressure of 10(-5) and 10(-2) mbar. No additional phases can be detected in the crystal, if the growth is perf ormed in air. The twins in the grown crystals are investigated using ultras ound-, optical-polarization-microscopy and Laue backscattering. In LaMnO3 w e find twin boundaries along the (1 1 2) and (1 0 1) planes. In La0.7Sr0.3M nO3 the twin boundaries are perpendicular to the pseudocubic(1 0 0) planes. (C) 2001 Elsevier Science B.V. All rights reserved.