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Shielding electrostatic fields in polar semiconductor nanostructures

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 Added by Gerald H\\\"onig
 Publication date 2016
  fields Physics
and research's language is English




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Modern opto-electronic devices are based on semiconductor heterostructures employing the process of electron-hole pair annihilation. In particular polar materials enable a variety of classic and even quantum light sources, whose on-going optimisation endeavours challenge generations of researchers. However, the key challenge - the inherent electric crystal polarisation of such materials - remains unsolved and deteriorates the electron-hole pair annihilation rate. Here, our approach introduces a sequence of reverse interfaces to compensate these polarisation effects, while the polar, natural crystal growth direction is maintained provoking a boost in device performance. Former research approaches like growth on less-polar crystal planes or even the stabilization of unnatural phases never reached industrial maturity. In contrast, our solution allows the adaptation of all established industrial processes, while the polarisation becomes adjustable; even across zero. Hence, our approach marks the onset of an entire class of ultra-fast and efficient devices based on any polar material.



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