Berlin 2018 – scientific program
HL 22.3: Talk
Tuesday, March 13, 2018, 14:30–14:45, EW 203
Correlation of structural and optical properties of GaN/AlN quantum disks embedded in nanowires by highly spatially cathodoluminescence microscopy — •Bowen Sheng1,2, Frank Bertram2, Ping Wang1, Xiaoxiao Sun1, Gordon Schmidt2, Marcus Müller2, Peter Veit2, Thomas Hempel2, Jürgen Christen2, and Xinqiang Wang1 — 1PKU, Beijing, China — 2IEP, OvGU, Magdeburg, Germany
Single photon emitters are the fundmental device applications in quantum optics and quantum information processing. Due to their large band offset and high binding energy of the excitons, III-nitrides quantum structures are most promising candidates for such devices. Despite the success in growing quantum dots, operating up to 300 K in 2014, the inherent piezoelectric fields, alloy fluctuations, shape and size control of the active region pose severe challenges with respect to fast and efficient generation of a single photon flux at a well-defined wavelength.
In this work, self-assembled hexagonally shaped GaN nanowires (NWs) with AlN/GaN/AlN quantum disk on top have been grown on Si (111) substrate in a dense array by plasma-assistant molecular beam epitaxy. To correlate the structural and optical properties of individual nanowires, highly resolved cathodoluminescence spectroscopy (CL) inside a scanning transmission electron microscope has been performed at 18 K along single NWs. CL linescans along the NWs clearly identify the emission coming from GaN bottom part around 359 nm and the GaN Q-disks around 347 nm with smallest FWHM of 60 meV, respectively. Other detailed analysis will be reported as well.