Novel ultrafast semiconductor lasers

Novel ultrafast semiconductor lasers Ursula Keller ETH Zürich SESAM modelocked VECSELs and MIXSELs are attractive semiconductor laser sources that deliver ultrashort laser pulses with picosecond and femtosecond pulse durations in combination with watt-level average output power levels in the gigahertz repetition rate range. The excellent beam quality and low-noise performance makes them highly attractive for several applications where they can replace conventional complex ion-doped diode-pumped solid-state lasers. The VECSEL and MIXSEL is part of the family of VCSELs which are the most frequently manufactured semiconductor lasers today. In contrast to a VCSEL a VECSEL (i.e. verticalexternal-cavity surface-emitting laser) has an external cavity and is either optically or electrically pumped. The optically pumped VECSEL is a successful commercial device produced by Coherent (i.e. OPSL). The MIXSEL (i.e. modelocked integrated external-cavity surface emitting laser) combines the gain of VECSELs with the saturable absorber of a semiconductor saturable absorber mirror (SESAM) in a single semiconductor device. Hence, self-starting and stable passive modelocking is obtained in a simple straight cavity formed by the semiconductor chip and a curved output coupler. This talk will give an overview of the recent advances in SESAM and graphene modelocked VECSELs, high-power picosecond and femtosecond MIXSELs, their excellent noise performance, frequency comb generation and optical and electrical pumping. Such sources have a great potential for the future vision of natural user interfaces (NUI). Gastgeber: Prof. Peter Michler, Universität Stuttgart, Telefon: 0711 685-64660