Related papers: Nonperturbative effects in second harmonic generat…
Two-dimensional (2D) materials with giant nonlinear optical (NLO) responses are essential for the development of advanced on-chip NLO devices. Using first-principles calculations, we predict a remarkable strain-induced enhancement of…
Recent experiments in the topological Weyl semimetal TaAs have observed record-breaking second-harmonic generation, a non-linear optical response at $2\omega$ generated by an incoming light source at $\omega$. However, whether…
We demonstrate a dramatic enhancement of supercontinuum generation (SCG) in H$_2$O driven by non-harmonic two-color laser fields, where pump and seed frequencies are not integer multiples. This scheme yields a broadband SC spectrum enhanced…
The topological Weyl semimetals with peculiar band structure exhibit novel nonlinear optical enhancement phenomena even for light at optical wavelengths. While many intriguing nonlinear optical effects were constantly uncovered in type-I…
We report on the experimental and theoretical investigation of magnetic-field-induced second harmonic generation (SHG) and two-photon absorption (TPA) of excited exciton states ($n \geq 3$) of the yellow series in Cu$_2$O. In this…
Second-order nonlinear optical processes do not manifest in the bulk of centrosymmetric materials, but may occur in the angstroms-thick layer at surfaces. At such length-scales, quantum mechanical effects come into play which could be…
Non-sequential double recombination (NSDR) high-order harmonic generation (HHG) is studied in a molecular system. We observe a unique molecular two-electron effect with a characteristic cutoff in the HHG spectrum at higher energies than…
Non-perturbative high-harmonic generation (HHG) has recently been observed in the liquid phase, where it was demonstrated to have a different physical mechanism compared to gas and solid phases of matter. The currently best physical picture…
Plasmonic nanostructures that support surface plasmon (SP) resonance potentially provide a route for the development of nanoengineered nonlinear optical devices. In this work, second-order nonlinear light scattering, specifically…
The emerging possibilities to steer and control electronic motion on subcycle time scales with strong electric fields enable studying the nonperturbative optical response and Bloch bands' topological properties, originated from Berry's…
We investigate the quantum evolution of the pump field in second-harmonic generation under strong pump depletion. Starting from a coherent state, the pump develops a nonclassical phase-space structure resembling a Schr\"odinger cat state.…
We demonstrate supermode-based second harmonic generation in an integrated nonlinear interferometer made of linear and nonlinear directional couplers. We use a fully-fibered pump shaper to demonstrate second harmonic generation pumped by…
We present a method, based on noncollinear second harmonic generation, to evaluate the non-zero elements of the nonlinear optical susceptibility. At a fixed incidence angle, the generated signal is investigated by varying the polarization…
We study the charge noise $S_Q$ in Josephson qubits produced by fluctuating two level systems (TLS) with electric dipole moments in the substrate. The TLS are driven by an alternating electric field of angular frequency $\Omega$ and…
We proposed a mechanism to generate giant anisotropic second harmonic nonlinear response via double resonance effect, achieved through band nesting via electronic bandstructure engineering. The ideal band setup would be a triplet of nested…
We report on the experimental observation of non-resonant, second-order optical Sum-Frequency Generation (SFG) in five different atomic and molecular gases. The measured signal is attributed to a SFG process by characterizing its intensity…
Optical-field sampling using second-harmonic generation (SHG) from strong-field ionization enables ultrabroadband terahertz detection, but the microscopic origin of the SHG signal and its ultrabroadband response have been unclear. Here we…
High-harmonic generation has emerged as a pivotal process in strong-field physics, yielding extreme ultraviolet radiation and attosecond pulses with a wide range of applications. Furthermore, its emergent connection with the field of…
Second-harmonic generation (SHG) has emerged as a promising tool for detecting electronic and magnetic structures in noncentrosymmetric materials, but 100$\%$ spin-polarized SHG has not been reported. In this work, we demonstrate nearly…
We present in detail the formulation of the ab initio theory we have developed for the calculation of the macroscopic second-order susceptibility $\chi^{(2)}$. We find a general expression for $\chi^{(2)}$ valid for any fields, containing…