Wyniki wyszukiwania - BazTech

1

Emission-intensity-enhanced GaN-based LED based on multilayer grating structures

Li Xin, Sun Dejie, Han Kun, Cao Lijun, Guo Shiliang, Li Zhiquan

Optica Applicata

|

2021

|

Vol. 51, nr 4

529--540

EN

A novel surface-plasmon-enhanced GaN-LED is proposed to improve the emission efficiency of the traditional LED. The SiO2 film, Ag triangular structure and ITO film were coated on the rectangularly-patterned p-GaN layer sequentially, which can form the quasi-symmetrical waveguide structure to enhance the internal quantum efficiency and the light extraction efficiency. The COMSOL software is used to simulate the LED structure. The radiated powers, absorbed powers and distribution of electric field are obtained and analyzed. The results reveal that emission efficiency of the proposed GaN-LED can be greatly improved.

2

Nanostructured targets for TNSA laser ion acceleration

Torrisi L., Calcagno L., Cutroneo M., Badziak J., Rosinski M., Zaras-Szydlowska A., Torrisi A.

Nukleonika

|

2016

|

Vol. 61, No. 2

103--108

EN

Nanostructured targets, based on hydrogenated polymers with embedded nanostructures, were prepared as thin micrometric foils for high-intensity laser irradiation in TNSA regime to produce high-ion acceleration. Experiments were performed at the PALS facility, in Prague, by using 1315 nm wavelength, 300 ps pulse duration and an intensity of 1016 W/cm2 and at the IPPLM, in Warsaw, by using 800 nm wavelength, 40 fs pulse duration, and an intensity of 1019 W/cm2. Forward plasma diagnostic mainly uses SiC detectors and ion collectors in time of fl ight (TOF) confi guration. At these intensities, ions can be accelerated at energies above 1 MeV per nucleon. In presence of Au nanoparticles, and/or under particular irradiation conditions, effects of resonant absorption can induce ion acceleration enhancement up to values of the order of 4 MeV per nucleon.

3

Influence of surface plasmon wave interference on near-field imaging on metal nanostructures with apertured probe

Yang Y., Sun Z.

Optica Applicata

|

2013

|

Vol. 43, nr 3

615--626

EN

We numerically studied artifact issues on near-field imaging of field intensity on metal nanostruc-tures (isolated ridges and slits in a continuous film) with an apertured probe. It is shown for the latter case that the interaction between neighboring slits via propagating surface plasmon waves (e.g., surface plasmon wave interferences) makes the probe-imaged field intensity highly condi-tional in reflection of the unperturbed field. As surface plasmon behaviors and probe imaging processes are polarization-sensitive and the field components are correlated, a model analysis of the partial field components elucidates their relations, which can help to derive the unperturbed near-field image from the probed one.

4

Further enhancement of light extraction efficiency of light-emitting diode with Ag film grown on photonic crystals

Chen J., Wang Q., Li H.

Optica Applicata

|

2011

|

Vol. 41, nr 1

51--61

EN

Photonic bandgap of photonic crystals (PCs) and the effect of grating diffraction can be used to improve the extraction efficiency of the light from a light-emitting diode (LED). The transmission of light at certain wavelength through periodic sub-wavelength hole arrays in metal films is extraordinary, because the surface plasmon acts effectively. In this letter, PCs with the square lattice of cylinder unit cells are placed in GaN layer of GaN-based blue LED, and the silver film is plated on PCs. The finite-difference time-domain (FDTD) method is used to investigate the optical transmission; the results show that the extraction efficiency of the PC-assisted LED (PC-LED) is enhanced when the silver film is plated on the PCs under certain conditions. Finally, we use the surface plasmon dispersion relation to analyze the mechanism of antireflection.