Electrical Detection of Quantum Dot Hot Electrons Generated via a Mn2+-Enhanced Auger Process

详细信息    查看全文

• 作者：Charles J. Barrows ; Jeffrey D. Rinehart ; Hirokazu Nagaoka ; Dane W. deQuilettesMichael Salvador ; Jennifer I. L. Chen ; David S. Ginger ; Daniel R. Gamelin
• 刊名：The Journal of Physical Chemistry Letters
• 出版年：2017
• 出版时间：January 5, 2017
• 年：2017
• 卷：8
• 期：1
• 页码：126-130
• 全文大小：386K
• ISSN：1948-7185

文摘

An all-solid-state quantum-dot-based photon-to-current conversion device is demonstrated that selectively detects the generation of hot electrons. Photoexcitation of Mn<sup>2+sup>-doped CdS quantum dots embedded in the device is followed by efficient picosecond energy transfer to Mn<sup>2+sup> with a long-lived (millisecond) excited-state lifetime. Electrons injected into the QDs under applied bias then capture this energy via Auger de-excitation, generating hot electrons that possess sufficient energy to escape over a ZnS blocking layer, thereby producing current. This electrically detected hot-electron generation is correlated with a quench in the steady-state Mn<sup>2+sup> luminescence and the introduction of a new nonradiative excited-state decay process, consistent with electron-dopant Auger cross-relaxation. The device’s efficiency at detecting hot-electron generation provides a model platform for the study of hot-electron ionization relevant to the development of novel photodetectors and alternative energy-conversion devices.