Plasma plume effects on the conductivity of amorphous-LaAlO₃/SrTiO₃ interfaces grown by pulsed laser deposition in O₂ and Ar

Amorphous LaAlO3/SrTiO3 interfaces exhibit metallic conductivity similarto those found for the extensively studied crystalline-LaAlO3/SrTiO3 interfaces. Here, we investigate the conductivity of the amorphous-LaAlO3/SrTiO3 interfaces grown in different pressures of O2 and Ar background gases. During the deposition, the LaAlO3 ablation plume is also studied, in situ, by fast photography and space-resolved optical emission spectroscopy. An interesting correlation between interfacial conductivity and kinetic energy of the Al atoms in the plume is observed: to assure conducting interfaces of amorphous-LaAlO3/SrTiO3, the kinetic energy of Al should be higher than 1 eV. Our findings add further insights on mechanisms leading to interfacial conductivity in SrTiO3-based oxide heterostructures

Polymyositis/Dermatomyositis: the current position

Polymyositis/dermatomyositis are a heterogeneous group of diseases characterised by skeletal muscle inflammation and necrosis.' 2 Since an excellent clinical description in 1903 by Steiner of dermatomyositis, which is essentially still valid,3 much progress has been made towards our understanding of this group of diseases. The most widely used clinical classification of idiopathic inflammatory myopathies is the one proposed by Bohan and Peter in 1975.4 That was a landmark, providing guidelines in clinical practice to accurate diagnosis of inflammatory myopathies and standardisation of studies. Nonetheless, the classification was based on clinical data. In view of recent histological and immunological studies the classification proposed by Karpati et al in 1987 seems better to fit our current view of such diseases5 (table 1). In this review we focus on recent developments in polymyositis/dermatomyositis, analysing separately the currently considered third major form of inflammatory myopathy-inclusion body myositis