Tunable semiconductor narrowband reflection filters for single frequency sources

Summary form only given. A novel temperature-tunable low-loss metal-semiconductor reflection filter operating in the 0.8-3 mum spectral range, at any incidence angle, is demonstrated. The filter devices are based on a Al(Ga)As/GaAs periodic quarterwave multilayer structure grown by low pressure metal organic chemical vapor deposition. The filters exhibit a theoretical reflectivity higher than 99% and a bandwidth as low as 300 GHz at -1% of R_max. The filter was tested with a V-shaped cavity VECSEL operating at 2.3 mum.