Center for Optical and Electromagnetic Research

Fort-de-France, Martinique

Center for Optical and Electromagnetic Research

Fort-de-France, Martinique

Time filter

Source Type

Jin Y.,Center for Optical and Electromagnetic Research | Jin Y.,Zhejiang University | Zhang P.,Center for Optical and Electromagnetic Research | Zhang P.,Zhejiang University | And 3 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

An electromagnetic energy squeezing mechanism is proposed based on the special properties of permeability-near-zero metamaterials. It is found that nearly no energy stream can enter a simply connected conventional dielectric material positioned inside a permeability-near-zero material. When the dielectric domain is shaped as a split ring (with a gap opened) surrounding a source, the electromagnetic energy generated by the source is forced to propagate through the gap. When the gap is narrow, the energy stream density becomes very large and makes the magnetic field enhanced drastically in the gap. The narrow gap can be long and bended. This provides us a method to obtain strong magnetic field without using resonance enhancement. © 2010 The American Physical Society.


Yu L.,Center for Optical and Electromagnetic Research | Zheng J.,Center for Optical and Electromagnetic Research | Dai D.,Center for Optical and Electromagnetic Research | He S.,Center for Optical and Electromagnetic Research | He S.,KTH Royal Institute of Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

Graphene, a well-known two-dimensional sheet of carbon atoms in a honeycomb structure, has many unique and fascinating properties in optoelectronics and photonics. Integration of graphene on silicon nanophotonic wires is a promising approach to enhance light-graphene interactions. In this paper, we demonstrate on-chip silicon nanophotonic wires covered by graphene with CMOS-compatible fabrication processes. Under the illumination of pump light on the graphene sheet, a loss reduction of silicon nanophotonic wires, which is called optically induced transparency (OIT) effect, is observed over a broad wavelength range for the first time. The pump power required to generate the OIT effect is as low as ~0.1mW and the corresponding power density is about 2×10 3mW/cm2, which is significantly different from the saturated absorption effect of graphene reported previously. The extremely low power density implies a new mechanism for the present OIT effect, which will be beneficial to realize silicon on-chip all-optical controlling in the future. It also suggests a new and efficient approach to tune the carrier concentration (doping level) in graphene optically. © 2014 SPIE.


Zhu Z.,Center for Optical and Electromagnetic Research | Qian J.,Center for Optical and Electromagnetic Research | Zhao X.,Zhejiang University | Qin W.,Hong Kong University of Science and Technology | And 6 more authors.
ACS Nano | Year: 2016

Organic fluorescent dyes with high quantum yield are widely applied in bioimaging and biosensing. However, most of them suffer from a severe effect called aggregation-caused quenching (ACQ), which means that their fluorescence is quenched at high molecular concentrations or in the aggregation state. Aggregation-induced emission (AIE) is a diametrically opposite phenomenon to ACQ, and luminogens with this feature can effectively solve this problem. Graphene oxide has been utilized as a quencher for many fluorescent dyes, based on which biosensing can be achieved. However, using graphene oxide as a surface modification agent of fluorescent nanoparticles is seldom reported. In this article, we used nanographene oxide (NGO) to encapsulate fluorescent nanoparticles, which consisted of a type of AIE dye named TPE-TPA-FN (TTF). NGO significantly improved the stability of nanoparticles in aqueous dispersion. In addition, this method could control the size of nanoparticles' flexibly as well as increase their emission efficiency. We then used the NGO-modified TTF nanoparticles to achieve three-photon fluorescence bioimaging. The architecture of ear blood vessels in mice and the distribution of nanoparticles in zebrafish could be observed clearly. Furthermore, we extended this method to other AIE luminogens and showed it was widely feasible. © 2015 American Chemical Society.


Cui Y.,Taiyuan University of Technology | Cui Y.,Center for Optical and Electromagnetic Research | Xu J.,Massachusetts Institute of Technology | Lin Y.,Taiyuan University of Technology | And 4 more authors.
Plasmonics | Year: 2013

In this paper, we employ an antireflective coating which comprises inverted π-shaped metallic grooves to manipulate the behaviour of a transverse-magnetic (TM)-polarised plane wave transmitted through a periodic nanoslit array. At normal incidence, such scheme cannot only retain the optical curtain effect in the output region but also generate the extraordinary transmission of light through the nanoslits with the total transmission efficiency as high as 90 %. Besides, we show that the spatially invariant field distribution in the output region as well as the field distribution of resonant modes around the inverted π-shaped grooves can be reproduced immaculately when the system is excited by an array of point sources beneath the inverted π-shaped grooves. Furthermore, we investigate the influence of centre groove and side-corners of the inverted π-shaped grooves on suppressing the reflection of light, respectively. Based on our work, it shows promising potential in applications of enhancing the extraction efficiency as well as controlling the beaming pattern of light emitting diodes. © 2013 Springer Science+Business Media New York.


Yu J.,Center for Optical and Electromagnetic Research | Yu J.,Lund University | Cai F.,Center for Optical and Electromagnetic Research | Cai F.,Lund University
Asia Communications and Photonics Conference, ACPC 2014 | Year: 2014

Being an excellent nonlinear nanomaterial, KNbO3 nanoneedles was used as XFROG nonlinear medium to measure the time/frequency-dependent intensity of a ~100 nm band dispersive wave, which was filtered from a super-continuum picoseconds pulse laser. © OSA 2014.


Dai D.,Center for Optical and Electromagnetic Research
Journal of Lightwave Technology | Year: 2012

A short polarization beam splitter (PBS) is presented based on an asymmetrical evanescent coupling system, which consists of a narrow input waveguide, a narrow output waveguide, and a wide middle optical waveguide between them. The width of the waveguides is designed so that the phase-matching condition is satisfied for the TM fundamental (MT 0) mode in the narrow input/output waveguide and the first higher order TM (MT 1) mode in the wide middle waveguide. Meanwhile, there is a significant phase mismatch for the case with TE polarization. Therefore, for the launched TE polarized light, almost no coupling happens when it goes through the coupling region and finally the TE polarized light is output from the through port. For the launched (MT 0) mode in the narrow input waveguide, it is completely coupled to the (MT 1) mode in the wide middle waveguide by choosing the optimal length of the coupling region. Furthermore, the (MT 1) mode excited in the wide middle waveguide is then coupled to the (MT 0) mode in the narrow output waveguide through the evanescent coupling between them. A short (~25μm long) PBS is designed based on silicon-on-insulator nanowires, while the gap width is chosen as large as 300 nm to make the fabrication easy. Numerical simulations show that the present PBS has a good fabrication tolerance for the variation of the waveguide width (more than ±20nm) and a broadband (~50nm) for an extinction ratio of >15dB. © 1983-2012 IEEE.


Shen Y.,Center for Optical and Electromagnetic Research | Yan C.,Center for Optical and Electromagnetic Research
2010 OSA-IEEE-COS Advances in Optoelectronics and Micro/Nano-Optics, AOM 2010 | Year: 2010

In recent years, water pollution detection has been global issues, especially for metal and organic pollution. And the phenomenon of ultrasonic cavitation has been widely used in the decades. In this paper, a method of detector water pollution by using sonoluminescence is introduced and some results are showed and analyzed.


Gaun X.,Center for Optical and Electromagnetic Research | Xu P.,Center for Optical and Electromagnetic Research | Shi Y.,Center for Optical and Electromagnetic Research | Dai D.,Center for Optical and Electromagnetic Research
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

An ultra-compact TE-pass polarizer with an ultra-broad band is proposed theoretically and demonstrated experimentally by utilizing a silicon hybrid plasmonic waveguide. The metal layer of the silicon hybrid plasmonic waveguide is designed to have an F-P cavity as well as a Bragg grating so that the TM-polarized light is reflected efficiently while the TE-polarized light goes through with very low loss. By utilizing the present structure with a metal Bragg grating, the designed TE-pass polarizer is with a size of as small as 0.5 × 3.1 I m2 and the theoretical extinction ratio is as high as 15 dB over a broad band of >200 nm. © 2014 SPIE.


Xu P.,Center for Optical and Electromagnetic Research | Yao K.,Center for Optical and Electromagnetic Research | Zheng J.,Center for Optical and Electromagnetic Research | Guan X.,Center for Optical and Electromagnetic Research | Shi Y.,Center for Optical and Electromagnetic Research
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

Two types of optical sensor based on one-dimensional Photonic Crystal (PhC) stack nanobeam cavity has been designed, fabricated and characterized. One-dimensional PhC stack nanobeam cavity with measured Q-factors up to 27000 and a sensitivity of 270nm/RIU has been demonstrated. Then, we introduce a finite width slot between two periodic arrays of the dielectric stacks. Thus, the majority of optical field distributes in the slotted low-index area and the light matter interaction with the analytes has been enhanced. A sensitivity of 410nm/RIU has been achieved while maintaining the Q-factors near 104. © 2014 SPIE.


Wang J.,Center for Optical and Electromagnetic Research | Chen S.,Center for Optical and Electromagnetic Research | Dai D.,Center for Optical and Electromagnetic Research
Optics Letters | Year: 2014

A monolithically integrated 64-channel hybrid demultiplexer on silicon is demonstrated experimentally to enable wavelength-division-multiplexing and mode-division-multiplexing simultaneously for realizing an ultra-large capacity optical-interconnect link. The present hybrid demultiplexer consists of a four-channel mode multiplexer realized with three cascaded asymmetrical directional-couplers and four identical arrayed-waveguide gratings (AWGs) with 16 channels. For the fabricated hybrid multiplexer, the excess loss and the crosstalk are about -7 and -10 dB, respectively. Better performances can be achieved by minimizing the imperfections (particularly in AWGs) in the fabrication processes. The present hybrid demultiplexer is scalable to have more channels by utilizing more wavelengths, modes, and polarizations. © 2014 Optical Society of America.

Loading Center for Optical and Electromagnetic Research collaborators
Loading Center for Optical and Electromagnetic Research collaborators