Fig. 4: Single-particle spectroscopy of single (11\(\overline{2}\)0)-attached homodimer and monomer.
a PL intensity trajectories of single monomer (gray), homodimer with 7.8 nm core-spacing (diatomic molecule, red), and homodimer with 11.4 nm core-spacing (double-QD, black) with background noises (soft gray in each plot). The binning time was 30 ms. b PL spectra with proper fittings of single monomer (gray), diatomic molecule (red), and double-QD (black). Inset in top plot, the polar graph of PL intensity of single monomer. Inset in middle plot, TEM image of a homodimer obtained after the single-particle spectroscopy measurements with a scale bar as 10 nm, the experiment was repeated 3 times. c Intensity ratios between PL1 and PL2 of single diatomic molecule vs. energy difference between PL1 and PL2 (ΔE) with a Boltzmann distribution fitting (black line). Inset: Energy difference (ΔE) of the mean and standard deviation for the homodimers (52 dimers), and Boltzmann distribution equation. d PL decay dynamics of a single diatomic molecule (red) and corresponding single monomer (black). Inset, the average lifetime and the PL QY. e A schematic illustration of the band-edge energy levels for diatomic molecule. f Rotation polarization angle dependent PL intensity (open circle) of PL1 (blue) and PL2 (green) for a single diatomic molecule, each of which is fitted with a sine function (solid lines). Inset: the polar graph of PL1 and PL2 intensity, with the PL2 intensity multiplied by 2 for better visibility. All optical measurements were performed at room temperature. Source data are provided as a Source Data file.
