Room-Temperature Transport of Indirect Excitons in (Al,Ga)N/GaN Quantum Wells
Room-Temperature Transport of Indirect Excitons in (Al,Ga)N/GaN Quantum Wells
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DOI：
10.1103/physrevapplied.6.014011
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发表时间：
2016-07-20
影响因子：
4.6
通讯作者：
Vladimirova, M.
中科院分区：
文献类型：
--
作者：
Fedichkin, F.;Guillet, T.;Vladimirova, M.
我们报道了激子在极性（Al，Ga）N/GaN量子威尔斯阱中的传播，量子阱的厚度超过几微米，温度可达室温。实现这一结果的关键因素是GaN衬底上生长的GaN量子威尔斯的晶体质量，它限制了非辐射复合。从光致发光的空间和时间动力学的比较，我们得出结论，在连续波激发下的激子的传播是由有效的屏蔽面内无序的帮助。漂移扩散形式主义内的建模证实了这一结论，并表明激子传播仍然是有限的激子散射缺陷，而不是激子-激子散射，使改善界面质量可以进一步提高激子输运。我们的研究结果为基于宽带隙极性异质结中栅控激子输运的室温激子器件铺平了道路。
We report on the exciton propagation in polar (Al,Ga)N/GaN quantum wells over several micrometers and up to room temperature. The key ingredient to achieve this result is the crystalline quality of GaN quantum wells grown on GaN substrate that limits nonradiative recombination. From the comparison of the spatial and temporal dynamics of photoluminescence, we conclude that the propagation of excitons under continuous-wave excitation is assisted by efficient screening of the in-plane disorder. Modeling within drift-diffusion formalism corroborates this conclusion and suggests that exciton propagation is still limited by the exciton scattering on defects rather than by exciton-exciton scattering so that improving interface quality can boost exciton transport further. Our results pave the way towards room-temperature excitonic devices based on gate-controlled exciton transport in wide-band-gap polar heterostructures.