Laser Safety (seminar by S. Guha, Aug. 30, 2019)


THG from RP-CsPbBr3 (J. Phys. Chem Lett. 2021)

Higher harmonic generation from perovskite nanocrystals

Lead halide perovskites provide a test bed for exploring nonlinear optical properties. Although the underlying centrosymmetric crystal structure of 3D lead halide perovskites precludes the phenomenon of second harmonic generation, the third and higher-order harmonic generation are allowed. The third harmonic generation (THG) from CsPbBr3 NCs with Ruddlesden–Popper planar faults (RP-CsPbBr3), formed via post-synthetic fusion-growth is enhanced with an effective third-order susceptibility of the order of 10–18 m2 V–2 .

EFISHG images from NLO films (unpublished)

Electric field-induced second harmonic generation imaging from organic devices

The application of an electric field is an effective mechanism for breaking the symmetry in otherwise symmetric molecular or other systems. Electric-field induced second harmonic generation (EFISHG) provides a tool for investigating chromophore orientation in nonlinear optical materials and understanding transport at the semiconductor-dielectric interface in thin film transistors.

Other projects

  • Fluorescence life time measurements using time-correlated single photon counting

  • Pump-probe transient absorption spectroscopy

  • Beam-shaping