Smith, Ryan P. Kim, Jong Su Lee, Sang Jun Noh, Sam Kyu Kim, Jin Soo Leem, Jae-Young Song, Jin Dong 2024-01-20T15:01:16Z 2024-01-20T15:01:16Z 2021-09-05 2012-05 0374-4884 https://pubs.kist.re.kr/handle/201004/129295 We investigate the effect of the quantum dot (QD) density on the thermal escape and the re-trapping processes of carriers for unstrained GaAs/AlGaAs QDs through temperature-dependent photoluminescence measurements. We fabricated high-density GaAs QDs (8.4 x 10(10)/cm(2), dot-dot distance similar to 34 nm) on an Al0.3Ga0.7As/GaAs (111) A surface by using droplet epitaxy. The average lateral size and height of the GaAs QDs are 24 and 6 nm, respectively. Temperature-dependent photoluminescence (PL) studies show that high-density GaAs QDs undergo a sigmoidal-shape energy shift. The sigmoidal dependence of the PL peak energy can be explained by thermal escaping of carriers followed by re-trapping by QDs. Our analysis indicates that the re-trapping probability of thermally-escaped carriers increases with decreasing dot-to-dot distance (corresponding to an increase in the QD density). English KOREAN PHYSICAL SOC LINE-SHAPE PHOTOLUMINESCENCE FABRICATION RELAXATION TIME Temperature Dependence of the Optical Properties of High-density GaAs Quantum Dots Article 10.3938/jkps.60.1428 1 JOURNAL OF THE KOREAN PHYSICAL SOCIETY, v.60, no.9, pp.1428 - 1432 JOURNAL OF THE KOREAN PHYSICAL SOCIETY 60 9 1428 1432 scie scopus kci ART001661829 000314808700001 2-s2.0-84863612009 Physics, Multidisciplinary Physics Article LINE-SHAPE PHOTOLUMINESCENCE FABRICATION RELAXATION TIME GaAs Quantum dots Optical properties Structural properties High-density QDs