Solid state amplified spontaneous emission in some spiro-type molecules: Anew concept for the design of solid state lasing molecules

Here are presented initial results on spectral narrowing in submicron thick neat films, of 2,2',7,7'-tetraphenyl-9,9'-spirobifluorene (spiro-quarterph enyl) and 2,2',7,7'-tetrakis(biphenyl-4-yl)-9,9-spirobifluorene (spiro-sexi phenyl). The luminescence effects reported here are common to several other molecules which belong the class of molecules known as the spiro-type mole cules. The Amplified Spontaneous Emission (ASE) is evidenced by a dramatic collapse of the line width, when pumped with sufficient energy, down to 2.2 and 2.9 nm for spiro-quarterphenyl and spiro-sexiphenyl, respectively. The se molecules have the ability to form stable, amorphous films with glass tr ansition temperatures at around 200 degrees C. Thus, these molecules are su itable candidates as the active material in molecular solid state injection lasers.