Single photon emitters, preferably working at room temperature, are crucial components of a diverse set of quantum technologies. Nanowire-supported quantum dots (NWQDs) of InGaN have emerged in the recent past as promising candidates of single photon emission (SPE) at visible wavelengths, though their efficient operation so far has been restricted to cryogenic temperatures. Here, we report the demonstration of visible-wavelength (λ=561 nm) SPE at room temperature, from specially designed InGaN NWQDs, wherein the second-order correlation function at zero-delay is measured to be the lowest reported so far (g2 (0) = 0.11), for this system. Using a single-step molecular-beam-epitaxy-based fabrication technique, we realized InGaN NWQDs with both lateral and vertical dimensions scaled down to the Bohr-radius limit. This achievement is responsible not only for the efficient single photon emission at room temperature but also for the reduction of carrier lifetimes to the order of several hundreds of picoseconds. The latter has been made possible by the suppression of the built-in polarization field, which is attributed to the strong radial confinement obtained in the NWQDs fabricated by our method. These InGaN NWQDs are thus extremely promising for the development of visible-wavelength single photon sources, operating at room temperature and GHz repetition rates.

中文翻译：

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室温下来自 GaN 纳米线中的 InGaN 量子点的超快绿光单光子发射


单光子发射器（最好在室温下工作）是多种量子技术的关键组成部分。纳米线支撑的 InGaN 量子点 (NWQD) 最近成为可见光波长单光子发射 (SPE) 的有前途的候选者，尽管迄今为止它们的有效运行仅限于低温。在这里，我们报告了专门设计的 InGaN NWQD 在室温下可见光波长（λ=561 nm）SPE 的演示，其中零延迟时的二阶相关函数被测量为迄今为止报道的最低值（g2 (对于该系统，0) = 0.11)。使用基于分子束外延的单步制造技术，我们实现了横向和垂直尺寸缩小至玻尔半径极限的 InGaN NWQD。这一成就不仅导致了室温下高效的单光子发射，而且还导致载流子寿命减少到数百皮秒的量级。后者是通过抑制内置偏振场而成为可能的，这归因于通过我们的方法制造的 NWQD 中获得的强径向限制。因此，这些 InGaN NWQD 对于开发在室温和 GHz 重复率下运行的可见波长单光子源非常有前景。