D
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Last name: DUBOZ
First name: Jean-Yves
International audience
Les propriétés germicides des rayonnements ultraviolets (UV) suscitent un intérêt de plus en plus important dans les domaines d'applications stratégiques que sont l'environnement et la santé. Les diodes électroluminescentes (LEDs) semi-conductrices à base de nitrure d'aluminium et de gallium représentent les nouvelles sources d'émission UV qui...
We modeled by kinetic Monte Carlo simulations the growth of InGaN alloys on perfectly oriented and misoriented GaN surfaces. As the growth temperature increases, we show that two phenomena occur: composition pulling along the growth direction and lateral indium rich cluster formation. We show that both phenomena have the same origin, strain,...
Here we use off-axis electron holography combined with advanced transmission electron microscopy techniques to understand the opto-electronic properties of AlGaN tunnel junction (TJ)-light-emitting diode (LED) devices for ultraviolet emission. Four identical AlGaN LED devices emitting at 290 nm have been grown by metal–organic chemical vapour...
In this work, we present the realization and the characterization of an optical waveguide made of AlN and GaN layers grown by MBE on Si(111) substrate. For the fundamental mode at 633nm, the propagation losses are in the order of 2 dB/cm, which is a good number for SC waveguides at this wavelength. The propagation losses dramatically increase...
The polarization of the light emitted by an ultraviolet light-emitting diode (LED) has a direct impact on the device performance: a transverse electric polarization of the emission is preferred for extraction from the surface of the diode grown along the c axis. While this is the case for most UV LEDs grown on AlN, this state of events could be...
We investigate the proton energy loss in GaN in an energy range between 0 and 65 MeV. The energy of protons generated by a cyclotron at about 65 MeV is varied by inserting an energyabsorbing medium of varying thickness. The precise modeling of the GaN Schottky diode response as a function of the absorbing medium thickness allows us to...
We investigate the proton energy loss in GaN in an energy range between 0 and 65 MeV. The energy of protons generated by a cyclotron at about 65 MeV is varied by inserting an energy- absorbing medium of varying thickness. The precise modeling of the GaN Schottky diode response as a function of the absorbing medium thickness allows us to...
International audience
Optical metasurfaces are becoming ubiquitous optical components to mold the amplitude, the phase and the polarization properties of light beams. So far, most of these devices are passive in essence, that is, they cannot be arbitrarily reconfigured or optimized according to the user's interest and/or change in their surrounding environment. Here...
International audience