Article
Optics
Yiwen Liu, Lili Gui, Kun Xu
Summary: The research investigates enhanced second-harmonic generation in gold Fano metasurfaces using nonlinear scattering theory. By introducing structural asymmetries, the second-harmonic signal is further amplified. Under optimal conditions, the previously suppressed SHG component is released, resulting in a 6-fold enhancement in total SHG intensity.
Article
Chemistry, Physical
Francois Aguillon, Andrei G. Borisov
Summary: In this work, the impact of atomic scale lattice imperfections on the nonlinear response of graphene nanoflakes enhanced by resonance between electromagnetic fields and localized plasmon is investigated theoretically. Using the many-body time-dependent density matrix approach, it is found that a single defect in nanoflakes with thousands of carbon atoms can significantly affect the nonlinear hyperpolarizability and override symmetry constraints. This effect cannot be captured by the relaxation time approximation in quantum or classical frameworks. The results of this study have important implications for the design of nonlinear graphene devices.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Yoshito Y. Tanaka, Tomoya Kimura, Tsutomu Shimura
Summary: A pair of V and Y-shaped gold nanoparticles are able to emit second harmonic (SH) radiation perpendicularly to the incident light direction, and the phase of this emission can be modulated by altering the shape of the Y-particle. This approach can be used to engineer directional nonlinear nanoantennas and nonlinear metamaterials.
Article
Chemistry, Multidisciplinary
Yoonsoo Rho, SeokJae Yoo, Daniel B. Durham, DongJun Kang, Andrew M. Minor, Costas P. Grigoropoulos
Summary: Nonlinear optical response is a useful tool for studying the properties of materials, but its weak signal and limited reach make it difficult to probe deep-subwavelength-scale nonlinear optics. In this study, we propose a new method using an SHG-active plasmonic nanotip to achieve efficient second harmonic generation (SHG) nanoscopy. Our simulations suggest that enhancing the nonlinear response of the sample or suppressing the tip's response can lead to a high near-field SHG contrast, providing evidence of quantum mechanical nonlinear energy transfer. Furthermore, this technique can be used to study nanoscale corrosion and other physicochemical phenomena.
Article
Chemistry, Multidisciplinary
Chentao Li, Xin Lu, Ajit Srivastava, S. David Storm, Rachel Gelfand, Matthew Pelton, Maxim Sukharev, Hayk Harutyunyan
Summary: This study presents the first experimental investigation of the nonlinear properties of monolayer transition metal dichalcogenides coupled to metal plasmonic nanocavities, showing a pronounced splitting in the pump-frequency dependence of the second-harmonic signal. Numerical simulations utilizing a nonperturbative nonlinear hydrodynamic model of conduction electrons support this interpretation and reproduce experimental results.
Article
Optics
Marc Jankowski, Carsten Langrock, Boris Desiatov, Marko Loncar, M. M. Fejer
Summary: We propose a new approach to supercontinuum generation and carrier-envelope-offset detection based on saturated second-order nonlinear interactions in dispersion-engineered nanowaveguides. The technique developed here broadens the interacting harmonics by forming stable bifurcations of the pulse envelopes due to an interplay between phase-mismatch and pump depletion. The scaling laws suggest that future realization based on this approach could enable supercontinuum generation with orders of magnitude less energy than current state-of-the-art devices.
Article
Chemistry, Multidisciplinary
Junjun Shi, Xiaobo He, Wen Chen, Yang Li, Meng Kang, Yangjian Cai, Hongxing Xu
Summary: A dual cavity resonance scheme with remote excitation is developed to significantly enhance SHG in a nanobelt system. The enhancement is achieved through the cooperation of plasmonic and FP cavity modes.
Article
Engineering, Electrical & Electronic
Kai Guo, Keya Zhou, Wei Liu, Zhongyi Guo
Summary: In this study, plasmonic toroidal dipole resonance was observed in core-shell nanodisks, leading to enhanced second harmonic generation (SHG). The frequency of this SHG is dependent on the refractive index of the dielectric core, with a red shift as the index increases. The findings could potentially contribute to the development of nonlinear nanooptics and their practical applications.
IEEE PHOTONICS JOURNAL
(2021)
Article
Nanoscience & Nanotechnology
Qing Leng, Huanhuan Su, Jianqiang Liu, Lin Zhou, Kang Qin, Qianjin Wang, Junqi Fu, Shan Wu, Xuejin Zhang
Summary: The study investigates the second-harmonic generation of monolayer transition metal dichalcogenides on suspended silver film, showing a significant enhancement of the SHG signal. The enhancement is attributed to the electric field amplification induced by symmetric surface plasmon polaritons (SPPs) in the silver grating.
Article
Optics
Chenglin Wang, Ran Shi, Lei Gao, Alexander S. Shalin, Jie Luo
Summary: In this study, it was found that the second-harmonic generation (SHG) from a tiny nonlinear particle can be greatly suppressed when placed near a subwavelength epsilon-near-zero (ENZ) particle. This quenching effect is due to the prohibition of electric fields near the ENZ particle caused by evanescent scattering waves, which is universal in both isotropic and anisotropic ENZ particles regardless of their shapes. Based on this principle, a dynamically controllable optical metasurface with switchable SHG quenching effect is proposed. This work enriches the understanding of optical nonlinearity with ENZ media and could have applications in optical switches and modulators.
PHOTONICS RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Fan Yang, Cristian Ciraci
Summary: We present a theoretical study on second-harmonic generation from a singular metasurface, which strongly interacts with incident light and generates intense surface polarization, resulting in the generation of second-harmonic field. By using transformation optics, the calculation of nonlinear optical response is simplified, and the dependence on the incident angle is weak, making it potentially useful for all-angle harmonic generation. Furthermore, we investigate the symmetry dependence of second-harmonic generation in the far field and demonstrate an enhanced conversion efficiency under normal incidence by breaking the surface inversion symmetry.
Article
Optics
Atsushi Sugita, Kanta Mochiduki, Yuhki Katahira, Soon Hock Ng, Saulius Juodkazis
Summary: In this study, an augmentation of Surface Plasmon (SP)-enhanced second harmonic generation (SHG) was presented using Au nanoprisms (AuNPs) with interference field enhancement. The SiO2 spacer layer contributed to optical interference and increased the coupling efficiency of pump light with SP polarization, as well as improved the decoupling efficiency of SHG waves from nonlinear polarization. By adjusting the thickness of the SiO2 spacer layer, the intensity of SP-enhanced SHG signals was significantly increased.
Article
Optics
Di Liu, Yingying Ren, Yanyan Huo, Yangjian Cai, Tingyin Ning
Summary: We numerically studied the linear and nonlinear optical responses in metasurfaces made of Au double-gap split ring resonators (DSRRs). We observed symmetry-protected dual bound states in the continuum (BICs) in these plasmonic metasurfaces at near-infrared optical frequencies. Efficient second harmonic generation (SHG) was achieved at the quasi-BIC modes due to symmetry breaking. Our results suggest that these plasmonic metasurfaces have great potential applications in on-chip efficient frequency conversion and linear and nonlinear chiral manipulation.
Article
Chemistry, Multidisciplinary
Xian-Xin Wu, Wen-Yu Jiang, Xiao-Feng Wang, Li-Yun Zhao, Jia Shi, Shuai Zhang, Xinyu Sui, Zhe-Xue Chen, Wen-Na Du, Jian-Wei Shi, Qian Liu, Qing Zhang, Yong Zhang, Xin-Feng Liu
Summary: We have developed an efficient inch-scale SHG source through a solution-processed method by assembling gold nanoparticles with porous anodic alumina templates. Our device achieves multiresonance in both visible and near-infrared regions, providing strong electric field enhancement at the gap region. The SHG radiation produced is polarization-independent and shows wide-angle nonlinear response thanks to the unique geometry of the nanostructure.
Article
Physics, Multidisciplinary
Xuecai Zhang, Junhong Deng, Mingke Jin, Yang Li, Ningbin Mao, Yutao Tang, Xuan Liu, Wenfeng Cai, Yao Wang, Kingfai Li, Yanjun Liu, Guixin Li
Summary: Nonlinear plasmonic metasurfaces have great potential for on-chip optical applications, but their low nonlinear response has been a limitation. A new design of nanocavity plasmonic metasurface was proposed in this study to enhance second-harmonic generation efficiency through strong light localization. This advancement may lead to highly efficient nonlinear metacrystals for various applications such as on-chip nonlinear sources and image encryption.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2021)
Article
Optics
Manfred Hammer, Lena Ebers, Jens Foerstner
Article
Optics
Manfred Hammer, Lena Ebers, Jens Foerstner
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2019)
Article
Physics, Applied
Amlan Mukherjee, Alex Widhalm, Dustin Siebert, Sebastian Krehs, Nandlal Sharma, Andreas Thiede, Dirk Reuter, Jens Foerstner, Artur Zrenner
APPLIED PHYSICS LETTERS
(2020)
Article
Materials Science, Multidisciplinary
Viktor Myroshnychenko, Stanislav Smirnov, Pious Mathews Mulavarickal Jose, Christian Brosseau, Jens Foerstner
Summary: In this study, the effective nonlinear dielectric response of a stochastic paraelectric-dielectric composite was investigated using different microstructure models and numerical calculation methods. The percolation threshold in the composite was found to govern the critical behavior of the effective permittivity and tunability, with tunability increasing as a function of dielectric phase concentration. The results provide insights into the distinct nonlinear behavior of 2D and 3D stochastic composites and can guide the design of novel composites with controlled morphology and tailored permittivity and tunability.
Article
Optics
Lena Ebers, Manfred Hammer, Jens Foerstner
Article
Optics
Manfred Hammer, Lena Ebers, Jens Foerstner
Summary: The study shows that Gaussian-beam-like bundles of semi-guided waves propagating in a dielectric slab can excite modes with high-order optical angular momentum supported by a circular fiber. Through a hybrid simulation, it is predicted that a substantial amount of input power can be focused into waves with specific orbital angular momentum.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2021)
Article
Optics
T. Leuteritz, H. Farheen, S. Qiao, F. Spreyer, C. Schlickriede, T. Zentgraf, V Myroshnychenko, J. Foerstner, S. Linden
Summary: This study presents a combined experimental and numerical investigation of the far-field emission properties of optical travelling wave antennas made from low-loss dielectric materials. The emission profile of the antenna is mainly determined by the director, while the reflector suppresses backward emission. Systematic studies show that the effective refractive index of the director primarily governs the far-field emission pattern.
Article
Physics, Applied
Alex Widhalm, Sebastian Krehs, Dustin Siebert, Nand Lal Sharma, Timo Langer, Bjoern Jonas, Dirk Reuter, Andreas Thiede, Jens Foerstner, Artur Zrenner
Summary: This research utilizes low capacitance single quantum dot photodiodes as sensor devices for optoelectronic sampling of ultrafast electric signals. By utilizing the Stark effect, time-dependent electric signals are converted into time-dependent shifts of transition energy, which are accurately measured using resonant ps laser spectroscopy with photocurrent detection. This technique allows for sampling transients below 20 ps with a voltage resolution in the mV-range.
APPLIED PHYSICS LETTERS
(2021)
Article
Optics
H. Farheen, T. Leuteritz, S. Linden, V Myroshnychenko, J. Foerstner
Summary: Optical traveling wave antennas, made from low-loss dielectric materials, have been numerically optimized for directivity using particle swarm optimization algorithm. The optimized antennas exhibit highly directional emissions and robust performance, making them excellent candidates for optical communication and sensing applications.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2022)
Article
Optics
Samer Alhaddad, Yevgen Grynko, Henna Farheen, Jens Foerstner
Summary: This study investigates the double-scattering coherent mechanism of negative polarization observed for powder-like surfaces near opposition. Numerical simulations reveal that double scattering between random irregular particles enhances negative polarization, and adding more particles further increases the polarization. Moreover, the interference mechanism is highly sensitive to the geometry of the scattering system.
Article
Optics
Manfred Hammer, Lena Ebers, Jens Foerstner
Summary: By processing narrow trenches on high-contrast silicon-photonics slabs, lossless power division for semi-guided waves can be achieved, with reflectance and transmittance configurable by selecting trench width. Devices at high angles of incidence are lossless, except for material attenuation and scattering, cascading trenches for 1xM-power dividers and polarization beam splitters is possible.
Article
Optics
Henna Farheen, Lok-Yee Yan, Viktor Quiring, Christof Eigner, Thomas Zentgraf, Stefan Linden, Jens Foerstner, Viktor Myroshnychenko
Summary: This paper presents the design and optimization of three broadband traveling-wave antennas with highly directive characteristics. Through full-wave simulations and global optimization, structures with enhanced directivity up to 119 radiation and low-loss properties are obtained, which are in good agreement with experimental measurements.
Article
Optics
L. Ebers, A. Ferreri, M. Hammer, M. Albert, C. Meier, J. Foerstner, P. R. Sharapova
Summary: In this paper, we theoretically demonstrate a flexible source of correlated photons built on the LNOI waveguide. The source has adjustable spectral properties and the number of frequency modes. The distinguishability in polarizations and spatial profiles enables the routing and manipulating of individual photons, while the equality of their group velocities eliminates the temporal walk-off between photons.
JOURNAL OF PHYSICS-PHOTONICS
(2022)
Article
Optics
Hamed Nikbakht, Mohammad Talebi Khoshmehr, Bob Van Someren, Dieter Teichrib, Manfred Hammer, Jens Foerstner, B. Imran Akca
Summary: In this paper, we present a new type of 3-dB coupler with an ultra-broadband operational range and low fabrication sensitivity. The coupler is asymmetric and utilizes tapered waveguides, resulting in a more wavelength-insensitive response compared to a standard coupler. Additionally, we demonstrate an optical switch using two of these couplers in a Mach-Zehnder interferometer configuration, which exhibits high extinction ratio over a specific wavelength range.
Article
Optics
Lena Ebers, Manfred Hammer, Manuel B. Berkemeier, Alexander Menzel, Jens Foestner
