title: Narrow emission linewidths of positioned InAs quantum dots grown on pre-patterned GaAs(100) substrates.
abstract: We report photoluminescence measurements on a single layer of site-controlled InAs quantum dots (QDs) grown by molecular beam epitaxy (MBE) on pre-patterned GaAs(100) substrates with a 15 nm re-growth buffer separating the dots from the re-growth interface. A process for cleaning the re-growth interface allows us to measure single dot emission linewidths of 80 µeV under non-resonant optical excitation, similar to that observed for self-assembled QDs. The dots reveal excitonic transitions confirmed by power dependence and fine structure splitting measurements. The emission wavelengths are stable, which indicates the absence of a fluctuating charge background in the sample and confirms the cleanliness of the re-growth interface.
authors.affiliation: Toshiba Research Europe Ltd, Cambridge Research Laboratory, Cambridge, UK. joanna.skiba@crl.toshiba.co.uk
authors.forename: Joanna
authors.initials: J
authors.lastname: Skiba-Szymanska
authors.forename: Ayesha
authors.initials: A
authors.lastname: Jamil
authors.forename: Ian
authors.initials: I
authors.lastname: Farrer
authors.forename: Martin B
authors.initials: MB
authors.lastname: Ward
authors.forename: Christine A
authors.initials: CA
authors.lastname: Nicoll
authors.forename: David J P
authors.initials: DJ
authors.lastname: Ellis
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Griffiths
authors.forename: David
authors.initials: D
authors.lastname: Anderson
authors.forename: Geb A C
authors.initials: GA
authors.lastname: Jones
authors.forename: David A
authors.initials: DA
authors.lastname: Ritchie
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Shields