High‐speed photoconductivity and infrared to visible up‐conversion in GaP light‐emitting diodes

Efficient infrared upconversion in Gap

Mechanisms for linear conversion of infrared to visible were investigated in extrinsic Gap. Efficient (1 %) conversion of 10 micron to visible was observed in GaP:Zn,O. Several device applications are discussed and a quantum counter scheme involving 111-V photocathodes is presented.

SATURATION BEHAVIOR OF EXTRINSIC PHOTOCONDUCTIVITY IN GaP LIGHT EMITTING DIODES AT HIGH INFRARED INTENSITIES

Saturation of extrinsic photoconductivity in GaP:N(Zn,Te) diodes could be achieved by excitation with a TEA-CO 2laser. At wavelengths in the IO ~m range intensities of several ]00 kW/cm 2 being near the damage threshold were applied. Carrier lifetimes of 60 ps at 4.2 K and 200 ps at 77 K could be estimated. The only conceivable mechanism explaining these short time constants is the capture of i...

Upconversion multicolor fine-tuning: visible to near-infrared emission from lanthanide-doped NaYF4 nanoparticles.

A general approach to fine-tuning the upconversion emission colors, based upon a single host source of NaYF4 nanoparticles doped with Yb3+, Tm3+, and Er3+, is presented. The emission intensity balance can be precisely controlled using different host-activator systems and dopant concentrations. The approach allows access to a wide range of luminescence emission from visible to near-infrared by s...

Mid-infrared upconversion spectroscopy

Visible cooperative upconversion laser in Er:LiYF(4).

We report trio upconversion laser action in Er:LiYF(4) with excitation at 1.55 microm resulting in cw emission at 0.55 microm to a temperature of 95 K and contrast its performance with earlier green erbium upconversion lasers.