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Related papers: On the second harmonic generation in superlattices

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We demonstrate unexpectedly strong second harmonic generation (SHG) in Argon gas by use of spatiotemporally focused (SF) femtosecond laser pulses. The resulting SHG by the SF scheme at a 75 cm distance shows a significantly enhanced…

We report optical second-harmonic generation (SHG) in reflection from GaSe crystals of 1 to more than 100 layers using a fundamental picosecond pulsed pump at 1.58 eV and a supercontinuum white light pulsed laser with energies ranging from…

Mesoscale and Nanoscale Physics · Physics 2017-10-10 Yanhao Tang , Krishna C. Mandal , John A. McGuire , Chih Wei Lai

We construct a family of bright optical solitons composed of fundamental frequency (FF) and second-harmonic (SH) components in the one-dimensional (planar) waveguide with the quadratic (second-harmonic-generating) nonlinearity and effective…

Pattern Formation and Solitons · Physics 2023-07-19 Pengfei Li , Hidetsugu Sakaguchi , Liangwei Zeng , Xing Zhu , Dumitru Mihalache , Boris A. Malomed

We aim to clarify the role that absorption plays in nonlinear optical processes in a variety of metallic nanostructures and show how it relates to emission and conversion efficiency. We define a figure of merit that establishes the…

High-harmonic generation in solids has emerged as a powerful probe of ultrafast electron dynamics and lattice motion, and recent theoretical work has suggested that thermally driven lattice fluctuations can act as an effective source of…

Lateral superlattices have attracted major interest as this may allow one to modify spectra of two dimensional electron systems and, ultimately, create materials with tailored electronic properties. Previously, it proved difficult to…

The laser interaction with an electron-positron-ion mixed plasma is studied, from the perspective of the associated high-order harmonic generation. For an idealized mixed plasma which is assumed with a sharp plasma-vacuum interface and…

Plasma Physics · Physics 2021-01-20 W. L. Zhang , T. Grismayer , K. M. Schoeffler , R. A. Fonseca , L. O. Silva

Polaritons can provide strong optical field enhancement allowing to boost light-matter interaction. Here, we experimentally observe enhancement of mid-infrared second-harmonic generation (SHG) using grating-coupled surface phonon polaritons…

The effect of slow light on second harmonic generation in a periodically poled $\chi^{(2)}$ nonlinear medium is investigated theoretically. A linear $\pi$ phase shifted grating is used to slow the group velocity of the fundamental frequency…

Optics · Physics 2022-02-02 Thomas E. Maybour , Devin H. Smith , Peter Horak

The generation of high-order harmonics in finite, hexagonal nanoribbons is simulated. Ribbons with armchair and zig-zag edges are investigated by using a tight-binding approach with only nearest neighbor hopping. By turning an alternating…

Mesoscale and Nanoscale Physics · Physics 2024-03-12 Hannah Jürß , Dieter Bauer

The mechanism of harmonic generation in both O and X-mode configurations for a magnetized plasma has been explored here in detail with the help of Particle-In-Cell (PIC) simulations. A detailed characterization of both the reflected and…

Plasma Physics · Physics 2021-10-27 Srimanta Maity , Devshree Mandal , Ayushi Vashistha , Laxman Prasad Goswami , Amita Das

Second harmonic generation in nonlinear materials can be greatly enhanced by realizing doubly-resonant cavities with high quality factors. However, fulfilling such doubly resonant condition in photonic crystal (PhC) cavities is a…

We consider the nonlinear response of a disordered two-dimensional electronic system, lacking inversion symmetry, to an external alternating electric field. The application of an in-plane static magnetic field induces local contributions to…

Mesoscale and Nanoscale Physics · Physics 2025-07-15 Maxim Dzero , Jaglul Hasan , Alex Levchenko

Strong second-harmonic generation has recently been experimentally observed from metamaterials consisting of periodic arrays of metal split ring resonators with an effective negative magnetic permeability [Science, 313, 502 (2006)]. To…

Materials Science · Physics 2012-05-22 Yong Zeng , Walter Hoyer , Jinjie Liu , Stephan W. Koch , Jerome V. Moloney

The resonant modes of optical cavities provide a powerful resource for laser-frequency stabilization, underpinning high-precision metrology and coherent signal generation. Photonic resonators in which the optical mode propagates through…

Optics · Physics 2026-02-12 Lindell M. Williams , Grant M. Brodnik , Scott B. Papp

In semiconductor superlattices, when Bragg oscillating electrons interact with an input electromagnetic field, frequency multiplication is possible. An ideal superlattice has a purely antisymmetric voltage current response and can thus…

Mesoscale and Nanoscale Physics · Physics 2019-01-29 Apostolos Apostolakis , Mauro F. Pereira

We develop a density matrix formalism in the length gauge to calculate the nonlinear response of intrinsic monolayer graphene at terahertz frequencies. Employing a tight-binding model, we find that the interplay of the interband and…

Optics · Physics 2014-12-17 Ibraheem Al-Naib , J. E. Sipe , Marc M. Dignam

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…

We demonstrate enhanced second harmonic generation in a gallium phosphide photonic crystal waveguide with a measured external conversion efficiency of 5$\times10^{-7}$/W. Our results are promising for frequency conversion of on-chip…

Optics · Physics 2015-05-28 Kelley Rivoire , Sonia Buckley , Fariba Hatami , Jelena Vuckovic

For a one-dimensional model in which the two-body interactions are long-range and strong, the system almost crystallizes. The harmonic modes of such a lattice can be used to compute the ground state wave function and the dynamical…

Strongly Correlated Electrons · Physics 2008-02-03 Diptiman Sen , R. K. Bhaduri
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