Anjali P S

Name of guide : Dr.Deepa Venkitesh
Year of Joining : 2017
Research topic : Fiber laser
Position : PhD
Background

  • Pursued MSc in Physics from University of Hyderabad
  • Pursued MS in Photonics through research from IIT Madras

Current Research
Thulium doped fiber laser (TDFL) operating in the 2 micron wavelength range has attracted considerable attention in the recent past due to its potential applications in spectroscopy, medicine and defence . Most of these applications require short pulses with high peak powers. My target is to build a high power thulium doped mode locked laser through passive mode locking with pulse width less than 100 ps.

The Laser Interferometer Gravitational-wave Observatory (LIGO) is the world’s first gravitational wave observatory to detect signals from distant astrophysical sources. The first observation of gravitational waves was made on September 14, 2015, 9:50:45 UTC, originating from the merging of two stellar-mass black holes. LIGO’s detector consists of two widely separated laser interferometers. Various kinds of noises such as seismic noise, thermal noise, laser noise could influence the detector’s sensitivity . Among the various noises mentioned, the laser noise is classified to intensity noise and phase noise that originates from the fluctuations of optical power and phase of laser light. The phase noise mainly originates because of random phase of photons added by spontaneous emission. The quantum noise associated with the optical loss also affects the phase noise of the laser. The phase noise of the laser is related to the frequency noise as well.A single frequency laser is necessary for high precision interferometry experiments. The phase noise of the laser leads to a finite laser line width and thus makes a single frequency laser not perfectly monochromatic. Hence a proper method for the characterization and then reduction of the phase noise is of great importance. Moreover, the proposed upgrades of the LIGO consist of an interferometer operating in the 2-micron wavelength region. Thus, the phase noise measurement and phase noise reduction technique for a 2-micron laser source would be very beneficial for the coming generation of LIGO detectors.So my target is to build a low noise high power 2-micron laser source.