PHYSICAL PROPERTIES AND TUNABLE LASER ACTION OF VERNEUIL GROWN SINGLE CRYSTALS OF Al2O3 : Ti3+ (Preliminary data) R. MONCORGE, P. PRADEL, F. CHATEL, G. BOULON, D. VIVIEN, A.M. LEJUS, R. COLLONGUES, V. DJEVAHIRDJIAN, K. DJEVAHIRDJIAN et R. CAGNARD J. Phys. Colloques, 48 C7 (1987) C7-389 DOI: 10.1051/jphyscol:1987793