Current Research

Quantum sensing with squeezed light

Squeezed light sources are a major success story in improving the sensistivity of gravitational wave detectors like LIGO. They allowed for suppression of quantum noise in the detectors below the standard quantum limit. This work primarily focusses on developing and refining the performance of squeezed light and extending its usability beyond the field of gravitational wave detectors. Squeezed light sources can potentially improve the the SNR in biomedical sensing techniques like stimulated Raman scattering microscopy, enhancing sensitivity of qunatum magnetometers, precision measurement of force and displacement, quantum radar and ranging.

Laser frequency and intensity stabilization

Improving the frequency and intensity stability is crucial for laser sources that are deployed in gravitational wave detectors. My work in this domain involves creating robust, low-noise syatems that can enhance the performance of the high power lasers that are used for long term interferometric measurements. The current work is focussed on improving the designing robust pre-mode cleaner cavity which filters the frequency, intensity and pointing noise in the laser source before it eneters the main interferometer in vacuum.

Optical modeling

This work focuses on the design and optimization of the complex coupled resonant cavities in interferometric gravitational wave detectors to investigate the design tolerances and improve the stability and performance of the detectors. Simulations are also done to understand the various noise sources affecting the overall detector sensitivity and test different noise mitigation techniques.

Past research

2015 - 2018

J R Macdonald Laboratory, Kansas State University, Kansas, USA.

• Molecular gas-filled hollow core optical fiber lasers
  Modeling, design and implementation. This work was motivated in exploring a new class of lasers that combines the merits of fiber lasers with gas lasers. The gases of interest include acetylene, HCN and alike that have laser emission wavelengths in the mid-IR making them versatile for eye safe laser applications.
• Fiber based frequency metrology
  This work investigates homemade gas cells made using photonic bandgap optical fibers that could be used as portable frequency references. Also the first phase investigations towards using fiber based infra-red frequency combs for precision spectroscopy of greenhouse gases was carried out.
• Dual comb Spectroscopy
  This project aimed at designing a portable instrument to perform frequency comb spectroscopy on agriculturally significant gases that have their molecular fingerprints in the mid-IR region.

2012 – 2015

California Institute of Technology, California, USA.

• Worked as part of the instrumentation group for the LIGO Scientific Collaboration, that made the breakthrough first direct detection of gravitational waves in 2015. My work was extensively in the assembly and commissioning for the 40 meter prototype interferometer at CalTech. The 40 meter is a controls prototype for the LIGO project working on interferometer control algorithms and serves as a test bed.
• Worked on research and development problems for the next generation of gravitational wave detectors.

2011 – 2012

Institute for Laser Science, The University of Electro-communications, Tokyo, Japan.

• Investigating properties of laser materials
• Simulation and study of thermal lensing in laser materials
• Ceramic laser cavity modeling and designing
• Building diode-pumped microchip lasers
• Modeling and designing Q-switched microchip ceramic lasers.