Strong Purcell enhancement at telecom wavelengths afforded by spinel Fe3O4 nanocrystals with size-tunable plasmonic properties

Ekaterina A Dolgopolova; Dongfang Li; Steven T Hartman; John Watt; Carlos Ríos; Juejun Hu; Ravi Kukkadapu; Joanna Casson; Riya Bose; Anton V Malko; Anastasia V Blake; Sergei Ivanov; Oleksiy Roslyak; Andrei Piryatinski; Han Htoon; Hou-Tong Chen; Ghanshyam Pilania; Jennifer A Hollingsworth

doi:10.1039/d1nh00497b

Strong Purcell enhancement at telecom wavelengths afforded by spinel Fe₃O₄ nanocrystals with size-tunable plasmonic properties

Nanoscale Horiz. 2022 Feb 28;7(3):267-275. doi: 10.1039/d1nh00497b.

Authors

Ekaterina A Dolgopolova¹, Dongfang Li¹, Steven T Hartman², John Watt¹, Carlos Ríos^{3

4}, Juejun Hu⁵, Ravi Kukkadapu⁶, Joanna Casson⁷, Riya Bose⁸, Anton V Malko⁸, Anastasia V Blake¹, Sergei Ivanov¹, Oleksiy Roslyak⁹, Andrei Piryatinski¹⁰, Han Htoon¹, Hou-Tong Chen¹, Ghanshyam Pilania², Jennifer A Hollingsworth¹

Affiliations

¹ Materials Physics and Applications Division: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. jenn@lanl.gov.
² Materials Science & Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
³ Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.
⁴ Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742, USA.
⁵ Department of Materials Science & Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
⁶ Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99354, USA.
⁷ Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁸ Department of Physics, The University of Texas at Dallas, Richardson, TX 75080, USA.
⁹ Department of Physics and Engineering Physics, Fordham University, Bronx, NY 10458, USA.
¹⁰ Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.

PMID: 34908075
DOI: 10.1039/d1nh00497b

Abstract

Developments in the field of nanoplasmonics have the potential to advance applications from information processing and telecommunications to light-based sensing. Traditionally, nanoscale noble metals such as gold and silver have been used to achieve the targeted enhancements in light-matter interactions that result from the presence of localized surface plasmons (LSPs). However, interest has recently shifted to intrinsically doped semiconductor nanocrystals (NCs) for their ability to display LSP resonances (LSPRs) over a much broader spectral range, including the infrared (IR). Among semiconducting plasmonic NCs, spinel metal oxides (sp-MOs) are an emerging class of materials with distinct advantages in accessing the telecommunications bands in the IR and affording useful environmental stability. Here, we report the plasmonic properties of Fe₃O₄ sp-MO NCs, known previously only for their magnetic functionality, and demonstrate their ability to modify the light-emission properties of telecom-emitting quantum dots (QDs). We establish the synthetic conditions for tuning sp-MO NC size, composition and doping characteristics, resulting in unprecedented tunability of electronic behavior and plasmonic response over 450 nm. In particular, with diameter-dependent variations in free-electron concentration across the Fe₃O₄ NC series, we introduce a strong NC size dependency onto the optical response. In addition, our observation of plasmonics-enhanced decay rates from telecom-emitting QDs reveals Purcell enhancement factors for simple plasmonic-spacer-emitter sandwich structures up to 51-fold, which are comparable to values achieved previously only for emitters in the visible range coupled with conventional noble metal NCs.