Optical properties of site-selectively grown inas/inp quantum dots with predefined positioning by block copolymer lithography

Paweł Holewa*, Jakub Jasiński, Artem Shikin, Elizaveta Lebedkina, Aleksander Maryński, Marcin Syperek, Elizaveta Semenova

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

43 Downloads (Pure)

Abstract

The InAs/InP quantum dots (QDs) are investigated by time-integrated (PL) and timeresolved photoluminescence (TRPL) experiments. The QDs are fabricated site-selectively by droplet epitaxy technique using block copolymer lithography. The estimated QDs surface density is ∼1.5 × 1010 cm−2 . The PL emission at T = 300 K is centered at 1.5 µm. Below T = 250 K, the PL spectrum shows a fine structure consisting of emission modes attributed to the multimodal QDs size distribution. Temperature-dependent PL reveals negligible carrier transfer among QDs, suggesting good carrier confinement confirmed by theoretical calculations and the TRPL experiment. The PL intensity quench and related energies imply the presence of carrier losses among InP barrier states before carrier capture by QD states. The TRPL experiment highlighted the role of the carrier reservoir in InP. The elongation of PL rise time with temperature imply inefficient carrier capture from the reservoir to QDs. The TRPL experiment at T = 15 K reveals the existence of two PL decay components with strong dispersion across the emission spectrum. The decay times dispersion is attributed to different electron-hole confinement regimes for the studied QDs within their broad distribution affected by the size and chemical content inhomogeneities.

Original languageEnglish
Article number391
JournalMaterials
Volume14
Issue number2
Pages (from-to)1-17
ISSN1996-1944
DOIs
Publication statusPublished - 2 Jan 2021

Bibliographical note

Funding Information:
Funding: This research was funded by the Villum Fonden via the NATEC Centre of Excellence under Grant No. 8692 and YIP QUEENs under Grant No. VKR023442. P.H. was funded by the National Science Centre (Poland) within the Etiuda 8 scholarship (Grant No. 2020/36/T/ST5/00511) and by the European Union under the European Social Fund. A.M. was funded by the National Science Centre (Poland) under Grant No. 2014/15/N/ST7/04708.

Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Keywords

  • Photoluminescence
  • Quantum dots
  • Site-selective growth

Fingerprint

Dive into the research topics of 'Optical properties of site-selectively grown inas/inp quantum dots with predefined positioning by block copolymer lithography'. Together they form a unique fingerprint.

Cite this