Temperature-dependent fine structure splitting in InGaN quantum dots

Journal article

We report the experimental observation of temperature-dependent fine structure splitting in semiconductor quantum dots using a non-polar (11-20) a-plane InGaN system, up to the on-chip Peltier cooling threshold of 200 K. At 5 K, a statistical average splitting of 443 ± 132 μeV has been found based on 81 quantum dots. The degree of fine structure splitting stays relatively constant for temperatures less than 100 K and only increases above that temperature. At 200 K, we find that the fine structure splitting ranges between 2 and 12 meV, which is an order of magnitude higher than that at low temperatures. Our investigations also show that phonon interactions at high temperatures might have a correlation with the degree of exchange interactions. The large fine structure splitting at 200 K makes it easier to isolate the individual components of the polarized emission spectrally, increasing the effective degree of polarization for potential on-chip applications of polarized single-photon sources.

Authors: Wang, T; Puchtler, T; Zhu, T; Jarman, J; Kocher, C

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: AIP Publishing
• Journal: Applied Physics Letters
• Volume: 111
• Issue: 5
• Article number: 053101
• Publication date: 2017-08-01
• Acceptance date: 2017-07-13
• DOI: 10.1063/1.4996861
• EISSN: 1077-3118
• ISSN: 0003-6951