We develop a theoretical model that describes the second harmonic generation of light from the surface of the topological insulatorBi2Se3 and experimentally demonstrate that the technique is sensitive to the surface electrons. By performing a crystal symmetry analysis of Bi2Se3(111) we determine the nonlinear electric susceptibility tensor elements that give rise to second harmonic generation. ...

The second harmonic generation from gold nanoparticles trapped into realistic and idealized gold nanoantennas is numerically investigated using a surface integral equations technique. It is observed that the presence of a nanoparticle in the nanoantenna gap dramatically modifies the second harmonic intensity scattered into the far-field. These results clearly demonstrate that second harmonic ge...

Nonlinear optical microscopy with sub-30 fs pulses from an Yb-fiber laser, approximately three times shorter than typical fiber laser pulses, leads to an order of magnitude brighter third harmonic generation imaging. Multiphoton fluorescence, second and third harmonic generation modalities are compared on stained microspheres and unstained biological tissues.

We demonstrate second harmonic generation performed with optical vortices with different topological charges imprinted on orthogonal polarizations. Besides the intuitive charge doubling, we implement arbitrary topological charge addition on the second harmonic field using polarization as an auxiliary parameter.

A model for the fifth-harmonic generation of pulsed IR lasers involving an external ring cavity resonating at the second harmonic has been developed. Numerical analysis is performed to show the relative effects of the pulse delay, input polarization, and orientation of the nonlinear crystals on the fifth harmonic power. The results are validated by published experimental results. The model is u...

The ability to see inside the body noninvasively is indispensable in modern biology and medicine. Optical approaches to such abilities are of rapidly growing interest because of their nonionizing nature and low cost. However, the problem of opacity due to the optical turbidity of tissues must be addressed before optical means become practical. Harmonic holography amalgamates the capability of h...