Article
Optics
Jinpeng Nong, Fu Feng, Changjun Min, Xiaocong Yuan, Michael Somekh
Summary: In this work, we propose a coupled borophene plasmonic system that can simultaneously excite anisotropic LP and DGP modes with exceptional flexibility in manipulating the optical response. The LP-DGP coupling can be passively adjusted by the spacer thickness and actively modulated by tuning the borophene electron density and incident angle, leading to a transparent window described by a coupled oscillation model.
Article
Optics
Peng Luo, Wei Wei, Guilian Lan, Xingzhan Wei, Liya Meng, Yan Liu, Juemin Yi, Genquan Han
Summary: The anisotropic PIT metamaterial device based on a graphene-black phosphorus heterostructure offers a dual-polarization tunable PIT effect, with the coupling strength of the system modulated by dynamically manipulating the Fermi energy of the graphene. This device provides additional degrees of freedom in realizing universal tunable functionalities, which could significantly promote the development of integrated optical processing chips, optical modulation, and slow light devices.
Article
Optics
Gongli Xiao, Zhixiong Lin, Hongyan Yang, Yanping Xu, Sitong Zhou, Haiou Li, Xingpeng Liu, Peihua Wangyang
Summary: This paper numerically investigates a tunable and anisotropic perfect absorber in a graphene-black phosphorus nanoblock array structure. The suggested structure exhibits polarization-dependent anisotropic absorption in the mid-infrared, and the absorption spectra can be tailored by adjusting the geometrical parameters and doping amounts. The results have the potential in the design of polarization-selective and tunable high-performance devices in the mid-infrared.
Article
Chemistry, Multidisciplinary
Prem Singh, Koustav Kundu, Sezer Seckin, Keshav Bhardwaj, Tobias A. F. Koenig, Amit Jaiswal
Summary: This paper reports a method for synthesizing gold Janus nanostars (NSs) that have a smooth pentagonal morphology with sharp tips and edges on one side and a crumbled morphology on the other. The synthesis method is different from other Janus nanoparticle preparation methods and does not involve template-assisted growth or masking techniques. The optical properties and size-dependent surface-enhanced Raman scattering (SERS) activity of the Janus NSs were investigated.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Review
Chemistry, Multidisciplinary
Nancy Khuu, Sina Kheiri, Eugenia Kumacheva
Summary: Structurally anisotropic hydrogels have shown promise as scaffolds for tissue engineering applications, by mimicking the structure and physical properties of anisotropic tissues in vivo and providing cells with appropriate signals. This review summarizes the biocompatibility, fabrication methods, characterization methods, and physical properties of anisotropic hydrogels and their impact on cell behavior, while also discussing future directions for development in tissue engineering applications.
TRENDS IN CHEMISTRY
(2021)
Article
Physics, Condensed Matter
Yu Zhou, M. N. Chen
Summary: Topological insulators (TIs) are materials with conductive surfaces but insulating bulk, suitable for plasmonic applications. This study extends the electromagnetic calculations to anisotropic TIs, finding two surface modes and providing potential applications for other surface conductive materials with similar symmetry.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Jun Zhang, Jinpeng Nong, Fu Feng, Changjun Min, Xiaocong Yuan, Michael Somekh
Summary: A hybrid plasmonic system was proposed in this study, which can simultaneously excite multi-order anisotropic borophene surface plasmons and magnetic polaritons. By tuning the resonant wavelengths to match each other, the absorption of borophene surface plasmons can be significantly improved, potentially finding applications in the design of boron-based optoelectronic devices in the infrared region.
RESULTS IN PHYSICS
(2021)
Article
Optics
Tingting Liu, Chaobiao Zhou, Shuyuan Xiao
Summary: The research on borophene in the field of two-dimensional materials has led to the proposal of a borophene-based absorption structure, which greatly enhances the interaction between light and borophene through a critical coupling mechanism. The structure demonstrates the light absorption performance of borophene, achieved controllable absorption behavior, providing a new approach for the application of borophene in electronic and photonic devices.
Article
Optics
Jinpeng Nong, Xin Xiao, Fu Feng, Bo Zhao, Changjun Min, Xiaocong Yuan, Michael Somekh
Summary: In this study, a coupled resonant system is proposed to simultaneously excite anisotropic borophene localized plasmonic and Bloch surface wave, allowing for exceptional flexibility in manipulating spectral response. A coupled oscillator model is used to quantitatively describe the observed BSW-BLP coupling, which can be flexibly tuned by adjusting the incident angle.
Article
Optics
Fangwei Han, Borong Yu, Chengxiang Zhao
Summary: The research demonstrates the anisotropic optical properties of Si3N4 microsphere arrays based on black phosphorus-like structure through simulations, showing that the anisotropy is caused by different local electric field distributions.
APPLIED PHYSICS B-LASERS AND OPTICS
(2022)
Article
Optics
Yong Li, Shiyu Wang, Yanghong Ou, Guoli He, Xiang Zhai, Hongjian Li, Lingling Wang
Summary: The study introduces a dynamically tunable anisotropic narrowband absorber based on monolayer black phosphorous and silicon grating in the terahertz band, featuring high absorption efficiency controlled by critical coupling conditions, exceptional tunability, intrinsic anisotropy, and ease of manufacturing.
Article
Multidisciplinary Sciences
Zi-Lan Deng, Tan Shi, Alex Krasnok, Xiangping Li, Andrea Alu
Summary: Experimental demonstration shows that electromagnetic skyrmions based on magnetic localized spoof plasmons exhibit high topological robustness, paving the way for the development of flexible sensors, wearable electronics, and ultra-compact antennas. These skyrmions maintain stability on materials of different shapes, demonstrating flexible texture characteristics.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Joseph Arnold Riley, Noel Healy, Victor Pacheco-Pena
Summary: The paper explores the applications of plasmonic lenses in controlling and manipulating the propagation of surface plasmons. Two different plasmonic lens structures are designed and evaluated, showing improved power enhancement compared to convex-planar lenses. The study also reveals a decrease in the depth of focus when using meniscus lenses.
SCIENTIFIC REPORTS
(2022)
Article
Optics
Hui Hu, Muxuan Geng, Zhaoqi Jiang, Hao Zhang, Zheng Zhu, Chunying Guan, Han Zhang, Jinhui Shi
Summary: The circular dichroism and circular birefringence responses of twisted black phosphorus nanostructures have been investigated, revealing their giant tunability in terms of geometrical and material parameters. This makes them attractive for constructing various black-phosphorus-based metamaterial devices.
Article
Physics, Applied
Zijian Zhang, Yuanzhen Li, Chi Wang, Su Xu, Zuojia Wang, Erping Li, Hongsheng Chen, Fei Gao
Summary: This article introduces a method for generating dispersion-tunable photonic topological waveguides without increasing material loss. The dispersion is tuned by changing the structure, and the experimental results validate the theoretical model.
APPLIED PHYSICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Alexander W. Powell, Rhiannon C. Mitchell-Thomas, Shiyu Zhang, Darren A. Cadman, Alastair P. Hibbins, J. Roy Sambles
Summary: Interlaced metallic meshes form a class of three-dimensional metamaterials that exhibit nondispersive, broadband modes at low frequencies. The experimental observation of these modes has been challenging, but the first experimental observation of the low frequency modes in a block of interlaced meshes fabricated through 3D printing has been reported. Antennas added to the meshes enable coupling of a plane wave to the low frequency dark mode, leading to the dispersion of the mode. Additionally, orthogonal antennas achieve polarization rotation and phase shifting of radiation passing through the structure. This work opens up possibilities for further experimental study into interlaced meshes and other complex 3D metamaterials.
Article
Engineering, Aerospace
Shishir Damani, Nathan Alexander, William J. Devenport, Benjamin P. Pearce, Samuel R. Shelley, Timothy A. Starkey, Alastair P. Hibbins, J. Roy Sambles
Summary: This experiment demonstrates the generation of trapped acoustic surface waves excited by a turbulent flow source through the coupling of pressure fluctuations at the interface between an acoustic metamaterial and a flow environment. The results show that the flow can be used to excite acoustic surface modes and their mode dispersion may be tailored toward realizing novel control of turbulent flow through acoustic-flow interactions. The study discusses the production, capture, and control process of acoustic surface modes through two different metasurface geometries.
Article
Physics, Applied
Alexander W. Powell, Alastair P. Hibbins, J. Roy Sambles
Summary: The superposition of resonances in a subwavelength particle can lead to powerful scattering beyond single channel limit and determine the directionality of scattered radiation. By overlapping modes with equivalent polarity in the far-field, a superbackscattering condition can be achieved, maximizing the total backscattered power. Additionally, overlapping multiple sets of modes can result in a multiband, superbackscattering effect.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
P. Petrov, A. P. Hibbins, J. R. Sambles
Summary: A fresh design approach for metamaterials formed by closely spaced helices has been developed based on retrieved values of electric and magnetic coupling coefficients between adjacent helices. Both numerical and experimental evaluations have been implemented to analyze coupling components between right- and left-handed helices in various arrangements, providing insights into the dependence of coupling strength on different factors. The study illustrates a geometry that allows for zero net-coupling between very close helices.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Multidisciplinary Sciences
Lauren E. Barr, Gareth P. Ward, Alastair P. Hibbins, Euan Hendry, J. Roy Sambles
Summary: This paper presents a low-loss, broadband slow wave that can be controlled through geometrical design. The dispersion characteristics of the mode are analyzed, and a frequency-dependent mode index is found. By placing a straight wire along the axis of the helix, the frequency range of near-constant mode index can be broadened.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Applied
Gregory J. Chaplain, Richard Craster, Nick Cole, Alastair P. Hibbins, Timothy A. Starkey
Summary: Research has shown that Scholte modes localized between a submerged axisymmetric structured elastic plate and surrounding fluid can be converted into radiative modes via Umklapp diffraction, with experiments confirming the focusing of underwater sound across a wide range of frequencies. This focusing phenomenon is achieved through structured beams forming a cone at a desired spatial position associated with an abrupt change in the patterning of the plate.
PHYSICAL REVIEW APPLIED
(2021)
Article
Optics
Alexander W. Powell, Michal Mrnka, Alastair P. Hibbins, J. Roy Sambles
Summary: This study demonstrates the design and behavior of subwavelength structures with multiple degenerate resonances at the same frequency. By carefully structuring a high-permittivity spherical shell with metallic or air core, mode superposition can be achieved, resulting in enhanced interaction with electromagnetic radiation and defined directivity. Experimental results show the suppression of backscattering and unidirectional antenna emission in the metallic core structure, while bidirectional antenna emission is maximized in the air core structure through the superposition of different modes.
Article
Physics, Applied
I. R. Hooper
Summary: This study demonstrates that increasing the light-matter interaction for millimeter waves using diffractively coupled waveguide modes significantly improves the photomodulation efficiency by more than two orders of magnitude, while maintaining the switching speed of the bare wafer.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Applied
I. R. Hooper, E. Khorani, X. Romain, L. E. Barr, T. Niewelt, S. Saxena, A. Wratten, N. E. Grant, J. D. Murphy, E. Hendry
Summary: In this paper, a new type of silicon-based metamaterial with a tunable electron-hole lifetime is designed, achieved by periodically patterning a dielectric surface passivation layer. The application of these metamaterials as photomodulators is investigated, with switching times depending on photoexcitation intensity, wafer thickness, and carrier lifetime.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Michal Mrnka, Ian R. Hooper, Harry Penketh, David B. Phillips, Euan Hendry
Summary: This paper presents a new design concept of dual-band spaceplate, which can simultaneously operate in two different frequency bands, enabling better utilization of spectral bandwidth. The design uses a multilayer stack of semitransparent mirrors separated by free-space voids to emulate the effect of free-space propagation, and the frequency separation can be adjusted to achieve different frequency bands.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2023)
Article
Materials Science, Multidisciplinary
J. K. Hamilton, M. Camacho, R. R. Boix, I. R. Hooper, C. R. Lawrence
Summary: In this study, the transmission properties of a nonperiodic array of slots arranged in the form of a Fibonacci sequence were investigated. It was found that this one-dimensional chain supports two periodicities, one due to the regular periodic separation and one due to the average spacing related to the golden ratio. The research also showed that the resonant behavior of a two-dimensional periodic array can be replicated by a single nonperiodic array, creating new families of diffraction lobes in the far-field region.
Article
Physics, Multidisciplinary
P. Petrov, A. P. Hibbins, J. R. Sambles, N. Aboulkhair, E. Saleh
Summary: This research presents a novel metasurface design comprised of capped helices arranged as a hexagonal array that supports a broadband near-isotropic negative-index microwave surface-wave. It demonstrates the ability to provide a structured surface that supports just a negative-index mode over a wide operational band with unprecedented bandwidth, without simultaneously exciting a forward wave. It is a significant advancement in the field of microwave technology.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
D. Osuna Ruiz, E. L. Martin, A. P. Hibbins, F. Y. Ogrin
Summary: A teardrop-shaped magnetic patch is proposed as a unidirectional magnetically driven spin wave emitter capable of operating in a wide range of frequencies. The system features reconfigurability and simplicity, allowing for control of wave emission through an external bias field.
Proceedings Paper
Engineering, Electrical & Electronic
Pavel Petrov, Alastair Hibbins, Roy Sambles
Summary: The Artificial Magnetic Conductor (AMC) is a type of metamaterial that enhances performance in various antenna and microwave design applications, and an analytical approach for size and bandwidth optimization of AMCs constructed of magnetically coupled elements is proposed in this work. Numerical results from COMSOL show that the optimized structure performs close to the theoretical limit.
2021 15TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2021)
Article
Materials Science, Multidisciplinary
T. J. Graham, J. D. Smith, A. P. Hibbins, J. R. Sambles, T. A. Starkey
Summary: Designer modes with negative or zero group velocities have applications in tailored wave propagation and energy redistribution. Experimental characterization of leaky Lamb modes in a thin flat aluminum-alloy plate submerged in water showed acoustic beaming from the plate caused by resonant transmission enhanced via intrinsic negative dispersion. Acoustic focusing properties depend on plate thickness and elastic material parameters and can be controlled for applications.
