Yangjie Liu

Hubei University · Faculty of Physics and Electronic Science

We propose a general method to arbitrarily manipulate the amplitude of an electromagnetic wave propagating in a two-dimensional medium, without introducing any scattering. This leads to a whole class of isotropic spatially varying permittivity and permeability profiles that are invisible while shaping the field magnitude. In addition, we propose a...

This manuscript proposes a two-dimensional heterogeneous imaging medium composed of an isotropic refractive index. We exploit conformal-mapping to transfer the full Maxwell fisheye into a finite circle. Unlike our previous design that requires a mirror of Zhukovski airfoil shape, this approach can work without a mirror, while offering a comparable...

In Čerenkov radiation and transition radiation, evanescent wave from motion of charged particles transfers into radiation coherently. However, such dissipative motion-induced radiations require particles to move faster than light in medium or to encounter velocity transition to pump energy. Inspired by a method to detect cloak by observing radiatio...

In this article we propose a new design methodology to control both amplitude and phase of electromagnetic waves from cylindrical incidence, which utilizes engineered media that does not resort to transformation optics or its quasi-conformal approximations. This method can lead to two-dimensional isotropic, inhomogeneous material profiles of permit...

Conventionally, space-charge (SC) limited current is defined as the maximal current allowed to traverse a diode under a DC voltage when a time-invariant current is injected from cathode. In this work, we study the SC limited current under the time-varying injection for both classical and relativistic regimes and determine the maximal amount of limi...

In this paper, we theoretically and experimentally demonstrate a three-dimensional metamaterial that can motivate electromagnetic induced transparency (EIT) by using circular polarized wave as stimulations. The unit cell consists of a pair of metallic strips printed on both sides of the printed circuit board (PCB), where a conductive cylinder junct...

We propose a general method to arbitrarily manipulate an electromagnetic wave propagating in a two-dimensional medium, without introducing any scattering. This leads to a whole class of isotropic spatially varying permittivity and permeability profiles that are invisible while shaping the field magnitude and/or phase. In addition, we propose a meta...

In this paper, we theoretically and experimentally demonstrate a three dimensional metamaterial that can motivate electromagnetic induced transparency (EIT) by using circular polarized wave as stimulations. The unit cell consists of a pair of metallic strips printed on both sides of the printed circuit board (PCB), where a conductive cylinder junct...

In this abstract for PHOTON' 16 submission, We give a general strategy to compute \v{C}erenkov radiation in a constant anisotropic medium (impedance matched), when the trajectory of electron bunch is prescribed. This simplifies the radiation computation and predict when such a medium gives null radiation~\footnote{Partial substance of this abstract...

This was accepted as a talk in Session 3, MNP III: Theory & Modelling, 16.30. I upload the slides for sharing purpose.

This is the extended version of the paper, updated in arxiv 2015.

We propose a new lens design via isotropic refractive index of heterogeneous medium. By aid of conformal map, one transfers the full Maxwell fisheye into a mapped profile within a unit circle. By this trick, the imaging resolution of this new profile is maintained as good as the mirrored Maxwell fisheye profile or its conformally-mapped counterpart...

A one-dimensional (1D) model has been constructed to study the transition of the time-dependent ultrafast laser photo-electron emission from a flat metallic surface to the space-charge-limited (SCL) current, including the effect of non-equilibrium laser heating on metals at the ultrafast time scale. At a high laser field, it is found that the spac...

Čerenkov radiation has hinted people since its birth as a basic observable phenomenon to unfold energy transfer from kinetic energy of moving electrons to electromagnetic waves, evanescent or traveling, whose physical principle is shared by transition radiation and Bremsstrahlung as well; whereas an emergent Transformation Optics strategy1 provides...

André Kurs et al. (2007) in Science 317, 83 titled Wireless Power Transfer via Strongly Coupled Magnetic Resonances, proposed a feasible scheme to near-field transfer electric energy. Here in this report we take note of our simulation on COMSOL 4.1.085 to repeat his counterpart in Chapter 4 of his master thesis. Due to huge requirement on memory si...

Čerenkov radiation has hinted people to unfold energy transfer from kinetic energy of moving electrons to electromagnetic waves, evanescent or traveling. However, such dissipative motion-induced radiations require particles to move faster than light in medium or to encounter velocity transition to pump energy. An emergent Transformation Optics stra...

Space charge limited current serves as a basic theoretical prediction for application of high current diodes and other vacuum electronics devices in field of non-neutral plasma physics. Classical Child-Langmuir law (CL law) analytically demonstrates maximum steady current density (space-charge-limited current density) transported before virtual cat...

Cerenkov radiation has hinted people since its birth as a basic observable phenomenon to unfold energy transfer from kinetic energy of moving electrons to electromagnetic waves, evanescent or traveling, whose physical principle is shared by transition radiation and Bremsstrahlung as well. However, such dissipative motion-induced radiations require...