Lee, Sang Jo Kim, Jong Su Byeon, Clare C. Kang, Hoonsoo Jeong, Mun Seok Song, Jin Dong Leem, Jae-Young Je, Koo-Chul Lee, Sang Jun Noh, Sam Kyu 2024-01-20T14:30:24Z 2024-01-20T14:30:24Z 2021-09-04 2012-08 0374-4884 https://pubs.kist.re.kr/handle/201004/129036 By using droplet epitaxy, we fabricated asymmetrically-coupled GaAs quantum dot molecules (AQDMs) and symmetrically-coupled GaAs concentric quantum-double rings (SCQRs). The geometrical coupling distances, dot-to-dot for the AQDMs and ring-to-ring for the SCQRs, were 30 nm and 28 nm, respectively. The photoluminescence (PL) measurement was performed with a femtosecond laser as an excitation source to investigate the structure-dependent optical properties of the AQDMs and the SCQRs as functions of the excitation intensity (corresponding to the injection carrier density). The excitation-power-dependent PL showed that the emission peak of the AQDMs was systemically red-shifted with increasing excitation intensity while the emission peak of the SCQRs was blue-shifted. The anomalous behavior in the shift of the emission peak for the AQDMs can be explained by using the inhomogeneous carrier distribution due to the geometrical asymmetry of the coupled QDs. English KOREAN PHYSICAL SOC DOTS FABRICATION Structural dependency of the optical properties of coupled GaAs quantum qots and rings Article 10.3938/jkps.61.455 1 JOURNAL OF THE KOREAN PHYSICAL SOCIETY, v.61, no.3, pp.455 - 459 JOURNAL OF THE KOREAN PHYSICAL SOCIETY 61 3 455 459 scie scopus kci ART001687052 000307441500025 2-s2.0-84866390280 Physics, Multidisciplinary Physics Article DOTS FABRICATION GaAs Coupled quantum dots Concentric quantum-double rings Optical properties Structural properties