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The ability to control electromagnetic fields on the subwavelength scale could open exciting new venues in many fields of science. Transformation optics provides one way to attain such control through the local variation of the permittivity…

Optics · Physics 2014-05-13 Bo Liu , Eric J. Heller

The author proposes the methodology of transformation optics in orthogonal coordinates to obtain the material parameters of the transformation media from the mapping in orthogonal coordinates. Several examples are given to show the…

Optics · Physics 2009-11-13 Huanyang Chen

Subwavelength atomic arrays, recently labeled as quantum metamaterials, have emerged as an exciting platform for obtaining novel quantum optical phenomena. The strong interference effects in these systems generate subradiant excitations…

Quantum Physics · Physics 2022-03-24 David Fernández-Fernández , Alejandro González-Tudela

Waveform inversion is theoretically a powerful tool to reconstruct subsurface structures, but a usually encountered problem is that accurate sources are very rare, causing the computation unstable and divergent. This challenging problem,…

Geophysics · Physics 2024-07-12 Han Yu

We establish results for the injectivity and injectivity modulo gauge of certain inverse source problems in transport on a simply connected domain with variable index of refraction inducing a 'simple geometry'. The model given by radiative…

Analysis of PDEs · Mathematics 2019-08-20 Guillaume Bal , François Monard

Stability is a key aspect of data analysis. In many applications, the natural notion of stability is geometric, as illustrated for example in computer vision. Scattering transforms construct deep convolutional representations which are…

Machine Learning · Computer Science 2018-11-28 Fernando Gama , Alejandro Ribeiro , Joan Bruna

We investigate the photon emission in coupled quantum dots based on symmetry considerations. With the help of a new theorem we proved, we reveal the origin of the various emission patterns, which is the combinative symmetry in the time…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 Shi-Fang Guo , Suqing Duan , Yan Xie , Wei-Dong Chu , Wei Zhang

In this Letter, we theoretically demonstrate that a uniform static electric field distribution can be partially converted to radiation fields when a portion of the medium undergoes a temporal change of its permittivity. An in-depth…

Wavefront shaping enables targeted delivery of coherent light into random-scattering media, such as biological tissue, by constructive interference of scattered waves. However, broadband waves have short coherence times, weakening the…

The condensation energy can be shown to be a moment of the change in the occupied part of the spectral function when going from the normal to the superconducting state. As a consequence, there is a one to one correspondence between the…

Superconductivity · Physics 2015-06-24 M. R. Norman , M. Randeria , B. Janko , J. C. Campuzano

Time varying media can dramatically modify the emission of embedded sources by producing time reversed waves refocusing on the source. Here we show that such a back action can create an angular momentum by setting the source in a…

Fluid Dynamics · Physics 2022-03-31 Samuel Bernard-Bernardet , Marc Fleury , Emmanuel Fort

The control of thermal radiation by shaping its spatial and spectral emission characteristics plays a key role in many areas of science and engineering. Conventional approaches to tailor thermal emission using metamaterials are severely…

We present the end-to-end design of compact passive and lossless metasurface (MTS) antennas with integrated feeds. The complete low-profile system consists of a single-layered reactive impedance MTS printed on top of a grounded dielectric…

Applied Physics · Physics 2022-03-10 Gengyu Xu , Vasileios G. Ataloglou , Sean V. Hum , George V. Eleftheriades

Inverse transformation optics is introduced, and used to calculate the reflection at the boundary of a transformation medium under consideration. The transformation medium for a practical device is obtained from a two-dimensional (2D)…

Optics · Physics 2014-03-31 Pu Zhang , Yi Jin , Sailing He

The on-axis cross-spectral density (CSD) of a beam radiated by a stationary source with a circular coherence state and a Gaussian spectral density is obtained in the closed form. It is revealed that the on-axis CSD is expressed via the…

Experiments provide a qualitative confirmation of significant absorption of a wide electromagnetic beam propagating along a thin conducting cylinder (the diameter of the cylinder can be orders of magnitude less than the beam waist width).…

Plasma Physics · Physics 2014-03-10 A. Akhmeteli , N. G. Kokodiy , B. V. Safronov , V. P. Balkashin , I. A. Priz , A. Tarasevitch

We derive the invariant imbedding equations for plane electromagnetic waves propagating in stratified magnetic media, where both dielectric and magnetic permeabilities vary in one spatial direction in an arbitrary manner. These equations…

Condensed Matter · Physics 2007-05-23 Kihong Kim , H. Lim , Dong-Hun Lee

Magnetic fields are constrained by the geometry and location of their sources, limiting the ability to freely tailor their spatial distribution. We introduce a general framework to passively convert the magnetic field generated by arbitrary…

We study Noncommutative Electrodynamics using the concept of covariant coordinates. We propose a scheme for interpreting the formalism and construct two basic examples, a constant field and a plane wave. Superposing these two, we find a…

High Energy Physics - Theory · Physics 2009-11-10 Jochen Zahn

We show how the dynamics of collisions between cold atoms can be manipulated by a modification of spontaneous emission times. This is achieved by placing the atomic sample in a resonant optical cavity. Spontaneous emission is enhanced by a…

Quantum Physics · Physics 2007-05-23 J. I. Kim , R. B. B. Santos , P. Nussenzveig.