All-optical photonic devices

Importance of acousto-optical devices in photonics as a modulator, Q-switch, passive-mode locker is well known. In these devices the acoustic signal or ultrasound is generated in a solid medium using an electronic signal applied to a transducer bonded to the acousto-optic medium. However, it is well-known that ultrasound can also be generated using high power light pulses incident on the medium. This method not only avoids the use of transducer and electronics associated with it but also has the potential of performing acousto-optic interaction in the terahertz regime using femto-sec pulses. Some preliminary experiments have been performed using LiNiO3 SAW delay line and a beam splitter. Results indicate that once optimized, these devices are useful and efficient.