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Flexible photodetectors (PDs) have received enormous interest owing to their potential applications in portable information technology and modern wearable optoelectronic devices. Herein, flexible solar-blind PDs based on amorphous Ga2O3 films fabricated on polyethylene naphthalate substrates at room temperature are demonstrated. The PD yields a responsivity up to 3.7 mA W−1, a fast response speed of 80 ms, a large detectivity of 1.14 × 1012 Jones, a high ultraviolet/visible rejection ratio of 6.1 × 103, and an ultra-high photo-to-dark current ratio over 105 at 10 V, which is comparable to the performance of a device on a rigid substrate. Moreover, the device exhibits no obvious performance degradation even after mechanical bending over 103 cycles, indicating an excellent stability. Our results pave the route for the realization of high-performance solar-blind optoelectronics with a flexible substrate.

We report observation of dispersion for coupled exciton-polariton in a plate microcavity combining with ZnO/MgZnO multi-quantum well (QW) at room temperature. Benefited from the large exciton binding energy and giant oscillator strength, the room-temperature Rabi splitting energy can be enhanced to be as large as 60 meV. The results of excitonic polariton dispersion can be well described using the coupling wave model. It is demonstrated that mode modification between polariton branches allowing, just by controlling the pumping location, to tune the photonic fraction in the different detuning can be investigated comprehensively. Our results present a direct observation of the exciton-polariton dispersions based on two-dimensional oxide semiconductor quantum wells, thus provide a feasible road for coupling of exciton with photon and pave the way for realizing novel polariton-type optoelectronic devices.

Single microbelt (MB) photodetectors with metal–semiconductor-metal structure have been demonstrated and characterized comprehensively. For single-photon absorption, the maximum responsivity of ZnO-MB photodetector can reach as high as 1.4 × 105 A W−1 at 20 V bias. The results about photoresponse of MB-detector reveals that two relaxation mechanisms contribute to the carrier decay time. Moreover, the two-photon absorption upconversion photoresponsivity in the single-MB detector has also been realized, which is the first report about the two-photon absorption detector to the best of our knowledge. The excellent two-photon absorption photoresponsivity characteristic of the MB device can be available not only for detector but also for solar cell and biomedical imaging. The above results present a significant step towards future fabrication of single micro/nano-structure based multiphoton excitation optoelectronic devices.