Extended Data Fig. 10: ANP (7% Tm3+) avalanche-shifting, pre-ANP (4% Tm3+) mechanobrightening, and piezochromic ANP (15% Tm3+) mechanochromism parameters versus excitation intensity.
From: Infrared nanosensors of piconewton to micronewton forces
Force range (a), force resolution (b), and noise-equivalent sensitivity (NES) (c), versus excitation intensity, derived from 26 compression cycles and 6 power-dependent compressions on six 4% Tm3+ pre-ANPs (grey), 23 compression cycles on nine 7% Tm3+ ANPs (teal), and 21 compression cycles on eight 15% Tm3+ piezochromic ANPs (purple). Different symbol shapes represent different single NPs. Each compression cycle consists of 10–1000 emission versus force data points, measured at 3 s (4% Tm3+), 3 s (7% Tm3+), and 3–50 s (15% Tm3+) integration times. Integration times for power-dependent compressions are 3–7 s per excitation power. Error bars represent S.E.M.s, propagated from the (integrated intensity versus force – for pre-ANPs and ANPs; 800 nm / 700 nm -emission ratio versus force – for piezochromic ANPs) linear fit value standard errors; compressions consisting of a lower number of emission-versus-force data points yield larger S.E.M.s. d. Summary of ICP-derived doping concentrations, TEM-derived NP sizes, and force measurement NES’s (mean ± standard deviation, for 3 single NPs measured at the same excitation intensity) for different sensing modalities.
