Sub-single exciton optical gain threshold in colloidal semiconductor quantum wells with gradient alloy shelling

Taghipour N., Delikanli S., Shendre S., Sak M., Li M., IŞIK F., ...Daha Fazla

NATURE COMMUNICATIONS, cilt.11, sa.1, 2020 (SCI-Expanded, Scopus) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 11 Sayı: 1
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1038/s41467-020-17032-8
  • Dergi Adı: NATURE COMMUNICATIONS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Agricultural & Environmental Science Database, BIOSIS, CAB Abstracts, Chemical Abstracts Core, EMBASE, Geobase, INSPEC, MEDLINE, Veterinary Science Database, Directory of Open Access Journals
  • Ankara Üniversitesi Adresli: Hayır

Özet

Colloidal semiconductor quantum wells have emerged as a promising material platform for use in solution-processable lasers. However, applications relying on their optical gain suffer from nonradiative Auger decay due to multi-excitonic nature of light amplification in II-VI semiconductor nanocrystals. Here, we show sub-single exciton level of optical gain threshold in specially engineered CdSe/CdS@CdZnS core/crown@gradient-alloyed shell quantum wells. This sub-single exciton ensemble-averaged gain threshold of (N-g)approximate to 0.84 (per particle) resulting from impeded Auger recombination, along with a large absorption cross-section of quantum wells, enables us to observe the amplified spontaneous emission starting at an ultralow pump fluence of similar to 800 nJ cm(-2), at least three-folds better than previously reported values among all colloidal nanocrystals. Finally, using these gradient shelled quantum wells, we demonstrate a vertical cavity surface-emitting laser operating at a low lasing threshold of 7.5 mu J cm(-2). These results represent a significant step towards the realization of solution-processable electrically-driven colloidal lasers.