Correlation effects in light sources with high quantum efficiency

There are several key requirements that a very good LED phosphor should meet, i.e., strong absorption, high quantum efficiency, high colour purity, and high luminescence quenching temperature. The reported Rb2Bi(PO4)(MoO4):Eu3+ phosphors have all these properties. The Rb2Bi(PO4)(MoO4):Eu3+ phosphors emit bright red light if excited with near-UV radiation. The calculated colour coordinates show good stability in the 77–500 K temperature range. Moreover, sample doped with 50% Eu3+ possesses quantum efficiency close to unity. Besides the powder samples, ceramic disks of Rb2Eu(PO4)(MoO4) specimen were also prepared, and the red light sources from these disks in combination with near-UV emitting LED were fabricated. The obtained results indicated that ceramic disks efficiently absorb the emission of 375 and 400 nm LED and could be applied as a red component in phosphor-converted white LEDs.

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Design and calculation of type-II superlattice resonant cavity-enhanced photodetector with high quantum efficiency and low dark current

Physica B Condensed Matter ◽

10.1016/j.physb.2021.413201 ◽

2021 ◽

pp. 413201

Author(s):

Ya-nan Du ◽

Lei Wang ◽

Yun Xu ◽

Guofeng Song

Keyword(s):

Quantum Efficiency ◽

Dark Current ◽

Resonant Cavity ◽

Type Ii ◽

High Quantum Efficiency ◽

High Quantum ◽

Type Ii Superlattice

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Modulation of optical properties of ZnS QDs embedded glasses through aluminum and manganese doping

Journal of Materials Chemistry C ◽

10.1039/d1tc02285g ◽

2021 ◽

Author(s):

Kai Li ◽

Ying Ye ◽

Wenchao Zhang ◽

Yuzhou Hu ◽

Ying Yang ◽

...

Keyword(s):

Optical Properties ◽

Quantum Efficiency ◽

High Quantum Efficiency ◽

Information Display ◽

Manganese Doping ◽

High Quantum

Nontoxic cadmium-free ZnS and ZnSe QDs QDs with high quantum efficiency have drawn considerable attention for information display. Applications of ZnS and ZnSe QDs are limited by their short emission...

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Highly Efficient Near-Infrared Detector Based on Optically Resonant Dielectric Nanodisks

Nanomaterials ◽

10.3390/nano11020428 ◽

2021 ◽

Vol 11 (2) ◽

pp. 428

Author(s):

Reza Masoudian Saadabad ◽

Christian Pauly ◽

Norbert Herschbach ◽

Dragomir N. Neshev ◽

Haroldo T. Hattori ◽

...

Keyword(s):

Quantum Efficiency ◽

High Speed ◽

Near Infrared ◽

Infrared Detector ◽

High Quantum Efficiency ◽

Fast Detection ◽

High Quantum ◽

Resonant Modes ◽

Infrared Wavelengths ◽

Dielectric Metasurface

Fast detection of near-infrared (NIR) photons with high responsivity remains a challenge for photodetectors. Germanium (Ge) photodetectors are widely used for near-infrared wavelengths but suffer from a trade-off between the speed of photodetection and quantum efficiency (or responsivity). To realize a high-speed detector with high quantum efficiency, a small-sized photodetector efficiently absorbing light is required. In this paper, we suggest a realization of a dielectric metasurface made of an array of subwavelength germanium PIN photodetectors. Due to the subwavelength size of each pixel, a high-speed photodetector with a bandwidth of 65 GHz has been achieved. At the same time, high quantum efficiency for near-infrared illumination can be obtained by the engineering of optical resonant modes to localize optical energy inside the intrinsic Ge disks. Furthermore, small junction capacitance and the possibility of zero/low bias operation have been shown. Our results show that all-dielectric metasurfaces can improve the performance of photodetectors.

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