Tip-Induced Strain Engineering of a Single Metal Halide Perovskite Quantum Dot

Autor: Yong-Hyun Kim, Dae Young Park, Sohee Jeong, Yeunhee Lee, Ju Young Woo, Hyeongwoo Lee, Jinseong Choi, Inho Jo, Jusun Park, Hyojung Kim, Mun Seok Jeong, Kyoung-Duck Park, Yeonjeong Koo
Rok vydání: 2021
Předmět:
Zdroj: ACS nano. 15(5)
ISSN: 1936-086X
Popis: Strain engineering of perovskite quantum dots (pQDs) enables widely tunable photonic device applications. However, manipulation at the single-emitter level has never been attempted. Here, we present a tip-induced control approach combined with tip-enhanced photoluminescence (TEPL) spectroscopy to engineer strain, bandgap, and the emission quantum yield of a single pQD. Single CsPbBrxI3-x pQDs are clearly resolved through hyperspectral TEPL imaging with ∼10 nm spatial resolution. The plasmonic tip then directly applies pressure to a single pQD to facilitate a bandgap shift up to ∼62 meV with Purcell-enhanced PL increase as high as ∼105 for the strain-induced pQD. Furthermore, by systematically modulating the tip-induced compressive strain of a single pQD, we achieve dynamical bandgap engineering in a reversible manner. In addition, we facilitate the quantum dot coupling for a pQD ensemble with ∼0.8 GPa tip pressure at the nanoscale estimated theoretically. Our approach presents a strategy to tune the nano-opto-electro-mechanical properties of pQDs at the single-crystal level.
Databáze: OpenAIRE