Related papers: General Theory for the Surface Second-Harmonic Gen…
We develop explicit expressions for the surface second-harmonic radiation yield using the three layer model. We derive expressions that can be applied to systems without and symmetry considerations, and then reduce them for the (111),…
Second-harmonic generation (SHG) is a second-order nonlinear optical process that is not allowed in media with inversion sym-metry. However, due to the broken symmetry at the surface, surface SHG still occurs, but is generally small. We…
Recent experiments and calculations in topological semimetals have observed anomalously strong second-order optical nonlinearity, but yet whether the enhancement also occurs at surfaces of topological semimetals in general remains an open…
Second harmonic generation (SHG) is forbidden in centrosymmetric molecular materials. However, a signal is frequently observed from interfaces where the symmetry is broken. Whereas the effect can be phenomenologically accommodated, an ab…
We conduct a theoretical and numerical study on the second-harmonic (SH) optical response of a nano-structured metamaterial composed of a periodic array of inclusions. Both the inclusions and their surrounding matrix are made of…
We discuss the susceptibility third-rank tensor for second harmonic and sumfrequency generation, associated with low index surfaces of silicon (Si(001), Si(011) and Si(111)) from two different approaches: the Simplified…
Optical second-harmonic generation (SHG) is studied for the confined geometry of a circular cylindrical waveguide or optical fiber. A model situation of high symmetry is considered where the material with nonlinear susceptibility is…
We theoretically investigate the second harmonic generation (SHG) of topological insulator surface states in a perpendicular magnetic field. Our theory is based on the microscopic expression of the second-order magneto-optical conductivity…
Second-harmonic-generation (SHG) in centrosymmetric material such as Si(111) is usually understood either from the phenomenology theory or more recently using the Simplified Bond-Hyperpolarizability Model (SBHM) [G. D. Powell, J. F. Wang,…
We revisit the mechanism of high harmonic generation (HHG) from solids by comparing HHG in laser fields with different ellipticities but constant maximum amplitude. It is shown that the cutoff of HHG is strongly extended in a circularly…
We study surface second-harmonic generation (SHG) from a singular plasmonic structure consisting of touching metallic wires. We use the technique of transformation optics and relate the structure to a rather simpler geometry, a slab…
Experimental insight into the elementary processes underlying charge transfer across interfaces has blossomed with the wide-spread availability of ultra-high vacuum set-ups that allow the preparation and characterization of solid surfaces…
We derive an expression for the effective second-harmonic coefficient of a dilute suspension of coated spherical particles. It is assumed that the coating material, but not the core or the host, has a nonlinear susceptibility for…
Successful phase-matching methods for Third Harmonics Generation (THG) include phase-matching in birefringent crystal and quasi-phase-matching (QPM) in crystal with periodically poled domains. However, these methods are not feasible in some…
We demonstrate phase-matched second-harmonic generation (SHG) from three-dimensional metamaterials consisting of stacked metasurfaces. To achieve phase matching, we utilize a novel mechanism based on phase engineering of the metasurfaces at…
We explore the outcomes of detailed microscopic models by calculating second- and third-harmonic generation from thin film surfaces with discontinuous free-electron densities. These circumstances can occur in structures consisting of a…
The double-layer potential plays an important role in solving boundary value problems for elliptic equations, and in the study of which for a certain equation, the properties of the fundamental solutions of the given equation are used. All…
The term "surface polarization" is introduced to describe the in-plane polarization existing at the surface of an insulating crystal when the in-plane surface inversion symmetry is broken. Here, the surface polarization is formulated in…
High harmonic generation (HHG) in solids has recently emerged as a powerful all-optical approach for probing material properties and ultrafast electron dynamics in quantum systems. It has been widely applied for studying two-dimensional and…
We present a combined experimental and theoretical study of enhanced third-harmonic generation (THG) in silicon nitride metasurfaces. These structures exhibit strong resonant nonlinear responses, enabling up to two orders of magnitude…