Article
Optics
Cizhe Fang, Qiyu Yang, Qingchen Yuan, Linpeng Gu, Xuetao Gan, Yao Shao, Yan Liu, Genquan Han, Yue Hao
Summary: A design with an array of slotted nanocubes is proposed to achieve significant second harmonic generation (SHG) from centrosymmetric silicon, which benefits from enlarged surface second-order nonlinearity and resonance enhancement. The experimentally measured SHG efficiency of the silicon slotted nanocube array is high and can be further improved by modifying the air-slot geometries. This result provides a new strategy to expand the nonlinear optical effects and devices of centrosymmetric materials.
LASER & PHOTONICS REVIEWS
(2022)
Article
Multidisciplinary Sciences
Xingchen Ji, Diana Mojahed, Yoshitomo Okawachi, Alexander L. Gaeta, Christine P. Hendon, Michal Lipson
Summary: The research introduces an OCT supercontinuum platform based on a Si3N4 photonic chip, capable of efficiently generating supercontinuum spectra near 1300 nm without postfiltering. By integrating the chip into an OCT system, high sensitivity and depth performance were achieved, paving the way for new opportunities in optical imaging technology.
Article
Chemistry, Multidisciplinary
Zhuojun Liu, Jiayi Wang, Bo Chen, Yuming Wei, Wenjing Liu, Jin Liu
Summary: Two-dimensional layered materials like GaSe have shown promise as novel nonlinear optical materials, but their nonlinear responses are limited by short interaction lengths with light. By coupling 2D GaSe flakes to silicon metasurfaces, a significant enhancement of second-harmonic generation (SHG) has been achieved, opening up new possibilities for high-power coherent light sources.
Article
Optics
F. Rodriguez-Hernandez, F. Grossmann, Jan M. Rost
Summary: In this study, we establish and analytically derive the cutoff law for high harmonics generated with two interfering electron wave packets in the continuum. We find that the cutoff arises from the maximal action difference of the dominant classical trajectories in the phase of the time-dependent dipole response. This interference between a maximally time-delayed stranded continuum trajectory and the trajectory of a high energy continuum electron makes the continuum-continuum harmonics more sensitive to electron wave-packet dispersion compared to standard high harmonics, suggesting their prominence in dimensionally reduced systems.
Review
Optics
Christian Lafforgue, Miguel Montesinos-Ballester, Thi-Thuy-Duong Dinh, Xavier Le Roux, Eric Cassan, Delphine Marris-Morini, Carlos Alonso-Ramos, Laurent Vivien
Summary: This article provides an overview of supercontinuum generation in silicon-compatible photonics platforms, including silicon, silicon germanium, and silicon nitride, as well as the essential theoretical elements to understand this phenomenon.
PHOTONICS RESEARCH
(2022)
Article
Astronomy & Astrophysics
I. H. Whittam, M. J. Jarvis, C. L. Hale, M. Prescott, L. K. Morabito, I Heywood, N. J. Adams, J. Afonso, Fangxia An, Y. Ao, R. A. A. Bowler, J. D. Collier, R. P. Deane, J. Delhaize, B. Frank, M. Glowacki, P. W. Hatfield, N. Maddox, L. Marchetti, A. M. Matthews, I Prandoni, S. Randriamampandry, Z. Randriamanakoto, D. J. B. Smith, A. R. Taylor, N. L. Thomas, M. Vaccari
Summary: In this study, we investigated the properties of the faint radio source population detected in the COSMOS field using the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) Early Science data, with a focus on the radio-loud active galactic nuclei (AGNs). Based on extensive multiwavelength data, we classified 88% of the 5223 radio sources in the field as AGNs or star-forming galaxies. We selected a sample of radio-loud AGNs with redshifts up to z~6 and studied their classification as high-excitation and low-excitation radio galaxies (HERGs and LERGs).
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Biochemistry & Molecular Biology
Chaiho Lim, Kwanghee Park, Yeongseok Chae, Kyungwon Kwak, Minhaeng Cho
Summary: This study overcomes the limitation of the spectral range in femtosecond time-resolved infrared spectroscopy by using a compact continuum mid-IR source. By building an IR spectrometer and correcting the distortion of the measured IR spectrum using bandpass filters, the researchers obtained an IR absorption spectrum consistent with a commercial FT-IR spectrometer. This work is of great practical value for future infrared spectroscopy experiments.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Astronomy & Astrophysics
B. Webster, J. H. Croston, J. J. Harwood, R. D. Baldi, M. J. Hardcastle, B. Mingo, H. J. A. Rottgering
Summary: The study confirmed the nature of nine potential galaxy scale jets using LOFAR data and discovered some galaxies that never grow beyond the GSJ stage. Analysis of spectral ages and lobe expansion speeds indicated that these GSJ have a significant impact on the evolution of the host galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Energy & Fuels
Zijing Wang, Xiaodong Zhu, Shuai Yuan, Xuegong Yu, Deren Yang
Summary: This paper investigates the formation and properties of swirl defects in Czochralski silicon solar cells and finds that these defects cause efficiency degradation. The swirl defects result in an energy level increase in the silicon bandgap and exhibit characteristics consistent with silicon/oxide interface states. Additionally, the swirl defects can evolve into stacking faults after annealing, leading to an additional energy level increase.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Materials Science, Multidisciplinary
Agnieszka L. Kozub, Arno Schindlmayr, Uwe Gerstmann, Wolf Gero Schmidt
Summary: Density-functional theory within a Berry-phase formulation is used to determine the second-order susceptibility of lithium niobate. Defect-trapped polarons and bipolarons enhance the nonlinear susceptibility of the material, especially when localized at specific defect pairs. This enhancement is due to the formation of polaronic states inside the band gap, allowing for spatial and transient modification of second-harmonic generation in macroscopic samples through illumination.
Article
Physics, Applied
Neetesh Singh, Manan Raval, Erich Ippen, Michael. R. Watts, Franz X. Kaertner
Summary: The study demonstrates strong signal generation within a supercontinuum generated in a silicon Bragg grating waveguide, with signal enhancement achieved at the Bragg resonance in the telecom window. This opens up avenues for research in nonlinear integrated photonics and signal enhancement through the Bragg effect.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Maximilian F. S. J. Menger, Qi Ou, Yihan Shao, Shirin Faraji, Joseph E. Subotnik, D. Vale Cofer-Shabica
Summary: Photoinduced processes are crucial in molecular phenomena, and accurate modeling requires considering the coupling between electronic states and energy flows with the environment, as well as the impact of nonadiabatic effects on energy exchange between electronic and nuclear degrees of freedom. In this study, a newly developed interface for non-adiabatic quantum mechanics/molecular mechanics in solvent (INAQS) is used to investigate the ring-opening reaction of 1,3-cylohexadiene in a solvent environment. The results highlight the solvent's role in the nonadiabatic relaxation process and the approach to equilibrium over time, revealing that gradients may not be relevant in highly multidimensional systems.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Energy & Fuels
Wei Long, Shi Yin, Fuguo Peng, Miao Yang, Liang Fang, Xiaoning Ru, Minghao Qu, Hongfeng Lin, Xixiang Xu
Summary: A numerical model based on Richter's theory has been developed to simulate the performance of SHJ solar cells, revealing a theoretical limiting efficiency of 28.5% with updated contact resistivities. The potential of solar cells with hybrid structures is demonstrated with a feasible 28.9% limiting efficiency achievable by combining p-type contact from SHJ and n-type contact from TOPCon.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2021)
Article
Nanoscience & Nanotechnology
Jared S. Ginsberg, Adam C. Overvig, M. Mehdi Jadidi, Stephanie C. Malek, Gauri N. Patwardhan, Nicolas Swenson, Nanfang Yu, Alexander L. Gaeta
Summary: The study introduces the use of an all-dielectric metasurface to enhance harmonic generation from surrounding gas with significantly improved results. Dielectrics are found to be more suitable for high power applications compared to metal nanostructures, especially when using atomic gases. By utilizing specially designed high-contrast gratings, a notable enhancement in third- and fifth-harmonic generation is achieved.
Article
Chemistry, Physical
Ning Tan, Hao Li, Zhao Ding, Kuixian Wei, Wenhui Ma, Dandan Wu, Shifeng Han
Summary: This study proposes a method of generating hydrogen by reacting silicon slag with water via wet grinding, which can be used in hydrogen production and application fields. It also suggests a scheme for purifying MG-Si by flotation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)