Article
Physics, Applied
Chao Qian, Hongsheng Chen
Summary: The topic of invisibility has long been of interest, but practical challenges remain. Combining metamaterials with deep learning shows promise as a way to address these challenges and develop intelligent, adaptive invisibility cloaks for dynamic environments. Future directions include further development in this area and the use of deep learning for other practice-oriented metadevices.
APPLIED PHYSICS LETTERS
(2021)
Article
Optics
Brian Slovick, Josh Hellhake
Summary: We proposed an optimization method for designing unidirectional invisibility cloaks by minimizing the forward scattering amplitude of the cloaked object. The use of the optical theorem simplifies the evaluation and integration of the scattering amplitude, making the optimization process computationally efficient. Several gradient-permittivity unidirectional cloaks were successfully designed to reduce scattering from metallic targets of varying sizes and shapes.
PHOTONICS RESEARCH
(2022)
Article
Multidisciplinary Sciences
V Kozlov, D. Vovchuk, P. Ginzburg
Summary: This study proposes a new method to address the issue of concealing targets from radar systems from a signal-processing standpoint.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Applied
Paris Ang, Gengyu Xu, George V. Eleftheriades
Summary: According to the Equivalence Principle, any distribution of electromagnetic fields can be generated within a closed region by suitable electric and magnetic sources located on its bounding surface. The development of Huygens's metasurfaces in recent years has enabled precise manipulation of electromagnetic waves through subwavelength thin sheets of artificial active and/or passive elements. This work aims to provide an overview of Huygens's metasurfaces with a focus on cloaking applications, detailing both active and passive Huygens's cloaks after discussing general operation and design principles.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
Z. C. Liu, X. B. Li, X. Cui
Summary: The study investigates the cloaking methods of infinite length coaxial cylindrical and concentric spherical invisibility cloaks in the non-uniform static field. An approaching cloaking method is proposed to achieve the optimal cloaking condition in a complex non-uniform static field, avoiding the iteration process. Three examples are given to verify the effectiveness of the analytical cloaking conditions and the approaching cloaking method proposed.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Multidisciplinary Sciences
Jun Cao, Fenghua Qi, Senlin Yan
Summary: Transformation acoustics provides a powerful tool for designing acoustic devices with excellent functionalities. This letter proposes a coordinate transformation methodology for achieving simplified parameters in the design of acoustic devices, leading to good performance in numerical simulations. The method opens up more opportunities for experimental realization of designed acoustic devices and can also be applied to 3D transformation-acoustic designs.
SCIENTIFIC REPORTS
(2021)
Article
Mathematics, Applied
Bo Wang, Zhiguo Yang, Li-Lian Wang, Shidong Jiang
Summary: This paper presents analytic formulas for temporal convolution kernel functions in non-reflecting boundary conditions for electromagnetic scattering problems, leading to efficient algorithms and accurate computations. It also introduces a new time-domain model for an electromagnetic invisibility cloak, optimizing accuracy and computational cost compared to existing models. The proposed method for simulating a spherical invisibility cloak demonstrates significant savings in computational time.
JOURNAL OF SCIENTIFIC COMPUTING
(2021)
Article
Optics
Tian Lu, Dantian Feng, Bo Fang, Pengwei Zhou, Dong Yao, Xufeng Jing, Chenxia Li, Haiyong Gan, Yingwei He, Jinhui Cai, Zhi Hong
Summary: By using a dielectric resonance cylindrical harmonic oscillator to construct the metasurface layer, it can reduce Ohmic loss, improve reflection efficiency, and optimize the design of carpet cloaking devices. This method can effectively cover various shapes of scatterers and confirm the cloaking effect through numerical simulations of near field and far field scattering characteristics.
LASER PHYSICS LETTERS
(2021)
Article
Optics
Ming Zhang, Najiao Zhang, Peng Dong, Lin Yang, Baozhu Wang, Ruihong Wu, Weimin Hou
Summary: With the rapid advancement of modern technology and radar detection systems, electromagnetic (EM) stealth technology has become increasingly significant, particularly in aircraft stealth and military radar applications. In this work, an all-metal metasurface is designed for broadband terahertz radar cross-section (RCS) reduction and infrared invisibility. The proposed method combines MATLAB and CST simulations with a genetic algorithm to optimize the random phase distribution of metasurfaces and achieve high performance. The results show that the metasurface can simultaneously achieve broadband terahertz RCS reduction and infrared invisibility in specific frequency ranges.
Article
Optics
Yan Shi, Meng Li, Xincui Gui, Chenxia Li, Xufeng Jing, Zhi Hong
Summary: Metasurfaces offer a new approach to achieve cloaking by manipulating electromagnetic wavefronts; using all-dielectric metasurfaces, a transmission stealth device can be created in free space, reducing transmission loss and enhancing efficiency, suitable for practical applications.
Article
Materials Science, Multidisciplinary
Fabio Sozio, Mostafa Faghih Shojaei, Arash Yavari
Summary: This paper presents a formulation of the optimal design of elastic cloaks based on the adjoint state method, enforcing the balance of linear momentum as a constraint. The design parameters are the elastic moduli of the cloak, and the objective function measures the distance between the solutions in the physical and virtual bodies. The proposed formulation can be easily extended to anisotropic solids. Numerical examples of optimal elastic cloaks designed for both single and multiple loads are provided, showing that in some cases, the optimal elastic cloaks for cloaking holes are made of auxetic materials.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Nanoscience & Nanotechnology
Alberto Miguel-Torcal, Jaime Abad-Arredondo, Francisco J. Garcia-Vidal, Antonio Fernandez-Dominguez
Summary: In this study, we investigate the generation of entanglement between two quantum emitters by inverse-design engineering of their photonic environment. We use a topology-optimization approach to create dielectric cloaks at different inter-emitter distances and incoherent pumping strengths. The structures obtained maximize the dissipative coupling between the emitters and yield steady-state concurrence values that are significantly higher than those achievable in free space. We demonstrate that the entanglement enabled by our devices approaches the limit of maximum-entangled-mixed-states.
Proceedings Paper
Engineering, Electrical & Electronic
Saeid Jamilan, Elena Semouchkina
Summary: Using the phenomenon of self-collimation in photonic crystals, the performance of invisibility cloaks made of dielectric rod arrays can be enhanced. By incorporating circular SC sections and TO-based transition sections in the cloak design, wave paths can be effectively controlled to reduce wave scattering and restore the original wavefront behind the hidden object.
METAMATERIALS XIII
(2021)
Article
Physics, Applied
Farhang Loran, Ali Mostafazadeh
Summary: This study provides a precise characterization of a higher-dimensional generalization of the unidirectional invisibility effect and identifies the conditions for its realization in scalar and electromagnetic wave scattering. The approach allows for the construction of potentials and linear dielectric media that exhibit perfect directional invisibility in a finite frequency domain.
APPLIED PHYSICS LETTERS
(2023)
Article
Multidisciplinary Sciences
Theodor S. Becker, Dirk-Jan Van Manen, Thomas Haag, Christoph Baerlocher, Xun Li, Nele Boersing, Andrew Curtis, Marc Serra-Garcia, Johan O. A. Robertsson
Summary: This paper presents a method for achieving active acoustic cloaking and holography without prior knowledge of the wavefield, allowing objects to remain invisible and illusions intact even for broadband moving sources. This opens up previously inaccessible research directions and facilitates practical applications such as architectural acoustics, education, and stealth.
