Date – 14th Sep, 2017 (Thursday)
Time – 4:00 pm
Venue – ESB 244
Speaker – Shree Krishnamoorthy (EE11D024)
Guides – Dr. Anil Prabhakar and Dr. Satyajit Mayor (NCBS)
Dr. Harishankar Ramachandran (Chairperson)
Dr. Ananth Krishnan (M)
Dr. Deepa Venkitesh (M)
Dr. Guhan Jayaraman (BT)
Dr. Sujatha.N (AM)
Mode locked fibre ring lasers can generate picosecond optical pulsewidths with MHz repetition rates. Applications in optical imaging, or in experiments with pump-probe lasers, benefit from being able synchronize two lasers at high repetition rates, while retaining the narrow optical pulse widths. An active mode locked fibre ring laser was designed as a slave laser for a picosecond pulsed laser application. The slave laser was locked by electrical injection to a master Ti:Sapphire laser operating at 80.07 MHz. However, changes in the wavelength of the master caused a detuning in the slaves fibre laser cavity. We investigate the increase in pulse width as a consequence of detuning. The pulsewidth increase was asymmetric about the ring cavity resonance frequency, a phenomenon that we were able to establish as a consequence of of lock-loss of the higher order cavity modes. The detuning range of the ring cavity decreases inversely to the mode number, in agreement with our theoretical predictions based on perturbative analysis of laser cavity injection locking.
Key words—Laser applications, laser modes, laser resonators, lasers, optical fiber lasers, injection locked oscillators, ring lasers, microscopy, pulsed lasers, synchronization.
Who will find the talk interesting – Pulsed lasers, laser applications, synchronization between systems like clocks, injection locked systems like PLLs, nonlinear microscopy and spectroscopy.
Expected background – Nothing much, maybe XII math.
All are cordially invited.