Photon Avalanche in Tm3+-Doped Nanocrystals: Towards Environmental Sensing in the Near-Field
Kevin Kwock, Columbia University
Tm ions have well-known energy levels spectroscopists often exploit for the study of fundamental photophysical properties in lanthanide systems. In our study, Tm-based avalanching nanoparticles (ANPs) were excited with a 1064nm CW laser and demonstrated substrate-dependent and environment-dependent upconversion power thresholds at which photon avalanching occurs. The heterogeneity of single ANPs emission was studied within this context and will be discussed. Furthermore, this initial study on single-particle ANPs motivates our continuing efforts to develop nanoscale materials relevant to nano-optical-based sensing techniques.
Nano-optical-based sensing can be achieved by conjugating a single ANP onto an atomic force microscope (AFM) tip. Förster resonant energy transfer (FRET) is a process in which the excited donor Tm ions in ANPs can then resonantly transfer their energy to acceptor materials, enabling nanoscale sensing and imaging. This technique, and other advanced development of near-field microscopy protocols, will be discussed as well.
We will report on our progress and collaboration across the three institutions, including our current efforts to carry out magneto-optical and other photoluminescence studies on ANPs at CINT.
Authors: Kevin W.C. Kwock1,5, Changhwan Lee2, Thomas Darlington2, Emanuil Yanev2, Matthew Strasbourg3, Artiom Skripka4, Ayelet Teitelboim4, Yawei Liu4, James C. Hone2, Nicholas Borys3, Bruce E. Cohen4, Emory Chan4, Ting Shan Luk6, Igal Brener6, Rohit P. Prasankumar7, Prashant Padmanabhan5, P. James Schuck2
1Department of Electrical Engineering, Columbia University, USA
2Department of Mechanical Engineering, Columbia University, USA
3Department of Physics, Montana State University, USA
4The Molecular Foundry, Lawrence Berkeley National Laboratory, USA
5Center for Integrated Nanotechnologies, Los Alamos National Laboratory, USA
6Center for Integrated Nanotechnologies, Sandia National Laboratories, New Mexico, USA
7Intellectual Ventures, USA
Abstract Author(s): (see above entries)