Ultralow-voltage operation of light-emitting diodes.


Change log
Authors
Lian, Yaxiao 
Xing, Shiyu 
Guo, Bingbing 
Ren, Zhixiang 
Abstract

For a light-emitting diode (LED) to generate light, the minimum voltage required is widely considered to be the emitter's bandgap divided by the elementary charge. Here we show for many classes of LEDs, including those based on perovskite, organic, quantum-dot and III-V semiconductors, light emission can be observed at record-low voltages of 36-60% of their bandgaps, exhibiting a large apparent energy gain of 0.6-1.4 eV per photon. For 17 types of LEDs with different modes of charge injection and recombination (dark saturation currents of ~10-39-10-15 mA cm-2), their emission intensity-voltage curves under low voltages show similar behaviours. These observations and their consistency with the diode simulations suggest the ultralow-voltage electroluminescence arises from a universal origin-the radiative recombination of non-thermal-equilibrium band-edge carriers whose populations are determined by the Fermi-Dirac function perturbed by a small external bias. These results indicate the potential of low-voltage LEDs for communications, computational and energy applications.

Description

Funder: National Natural Science Foundation of China (National Science Foundation of China); doi: https://doi.org/10.13039/501100001809


Funder: RCUK | Engineering and Physical Sciences Research Council (EPSRC); doi: https://doi.org/10.13039/501100000266

Keywords
Article, /639/301/1005, /639/624/1020, /639/766/1130, /639/925/357/995, /639/4077/4072/4062, /120, /128, /139, /129, article
Journal Title
Nat Commun
Conference Name
Journal ISSN
2041-1723
2041-1723
Volume Title
Publisher
Springer Science and Business Media LLC