• Optical parametric oscillators (OPO):

As part of my PhD research, I am working on developing a high repetition rate mid-infrared coherent source using second-order nonlinear optical processes, specifically optical parametric oscillator (OPO) and optical parametric amplification (OPA). In this project, I have successfully built and demonstrated both continuous wave and femtosecond OPOs in the lab. If you have any questions about constructing an OPO, including aspects like beam waist calculations or cavity alignment, feel free to reach out to me via email—I’d be happy to assist. 

• Hilbert's Hotel realisation using fractional vortex beam:

The mathematics of infinity seems to be paradoxical and counterintuitive, but they have many real-world realisations and applications. In 1924, mathematician David Hilbert illustrated the strange nature of the actual infinity which tell us to imagine a hotel now known as the "Hilbert Hotel" which has an infinite number of rooms in it. Furthermore, he says that imagine every room is occupied by a guest. Now suppose one night, a new guest appears in the hotel and wants to check in. It seems that there will be no room for the new guest in the Hilbert Hotel, however, David Hilbert suggested that the manager can vacant a new room by asking the existing customers in the hotel to come out of their room and moved to the next highest room (say the person in room #1 moved to room #2, the person in room #2 moved to room #3) and thereby creating a new vacancy at room #1 in the hotel.

One would intuitively think that there will be no place for such strange nature of countable infinity in the real world. However, in 2004 Prof. M.V. Berry and later in 2016 Prof Gerg Gbur, pioneers in the field of SingularOptics, theoretically showed us that the fractional optical vortex near its half-integer can manifest the Hilbert hotel. we show the first experimental demonstration of the optical Hilbert Hotel in both the phase and polarisation singular optical beams. In collaboration with Prof Greg Gbur, using a supercontinuum laser source from SuperK EVO NKTPhotonics and a single spiral phase plate, we showed that the fractional optical Vortex and Vector beams mimic the exact Hilbert Hotel behaviour.