Volume 15 Issue 9, September 2021

Low stability of perovskite light-emitting diodes (PeLEDs) is the biggest obstacle to the commercialization of PeLED displays. Here, we cover the current status and challenges in analysing and improving the stability of PeLEDs and suggest some advice that will benefit the community to boost the operational lifetime of PeLEDs.

Franky So, from North Carolina State University, explains some hard truths for solution-processed emitters, but also that, fundamentally, there is no reason why OLEDS can’t ‘make it’.

Nature Photonics spoke to Chihaya Adachi from the Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, about the potential merits of, and hurdles facing, the development of organic semiconductor lasers.

A simple yet effective optical set-up, employing two controllable, indistinguishable photons, is proven to allow a direct measurement of the exchange phase due to the bosonic particle statistics.

Electromagnetic confinement in optical resonators of diminishing dimensions has enabled unprecedented light–matter interaction strengths. This miniaturization trend has a nonlocal limit, which, surprisingly, originates from the matter excitations rather than the light.

Photon propagation through an array of coupled waveguides arranged in various fractal patterns serves as a useful ‘optical simulator’ for revealing insights into quantum transport in complex scenarios.

Colloidal quantum dots may offer solution-processable lasers, with a wide range of colours available. Technical hurdles and progress towards realization of useful quantum dot laser diodes is reviewed.

A summary of recent advances in the near-infrared light-emitting diodes that are fabricated by solution-processed means, with coverage of devices based on organic semiconductors, halide perovskites and colloidal quantum dots.

An interferometric technique is developed to measure the particle exchange phase of indistinguishable photons. The exchange phase obtained is (−0.04 ± 0.07) radians, which clearly demonstrates the symmetric nature of the two-photon wave functions.

A collective coherent quantum many-body phase, namely superfluorescence, is observed in CH₃NH₃PbI₃ at 78 K. The excitation fluence dependence of the spectroscopic features and the population kinetics confirm all its well-known characteristics.

The use of a dimensionally graded 2D perovskite interface and passivation results in perovskite solar cells with very low photovoltage loss.

Extreme electromagnetic field confinement in polaritonic systems is demonstrated. The tight fields can excite magnetoplasmons and result in nonlocal phenomena.

Tin-based perovskite nanocrystals with slower than usual relaxation dynamics holds promise for superior lead-free perovskite optoelectronic devices.

Quantum transport in fractal networks is experimentally investigated by performing continuous-time quantum walks in fractal photonic lattices. Contrarily to classical fractals, anomalous transport governed solely by the fractal dimension is observed.