Michel Papuchon

Optical levitation using single mode fibers and its application to self‐centering of microlenses

Optical levitation using single mode fibers has been experimentally demonstrated. The use of fibers in levitation experiments presents obvious advantages, in particular, concerning the case with which complicated optical paths can be realized without additional optical components. In addition the microsphere can be accurately deposited on the fiber end by simply controlling the optical guided power. This technique has been used to position microlenses self‐centered on the guided mode to improve the coupling efficiency between a semiconductor laser and a single mode fiber.

Seeding of a titanium sapphire oscillator by a vertical‐cavity surface‐emitting laser in the nanosecond range

A GaAs/AlGaAs vertical‐cavity surface‐emitting laser was used to seed a titanium‐sapphire laser oscillator. Both lasers were pumped synchronously by the same frequency‐doubled Nd:YAG laser in the nanosecond range. Even at low injection level, we obtained a strong narrowing of the emission spectrum of the oscillator (from 30 to 1 nm), as well as its tunability over a broad range of wavelengths (from 775 to 805 nm).