Idus 420

The fluorescence quantum yields were measured and determined according to the procedure described in^{47 (link)}. The measurements on SCP were carried out at room temperature using a laser diode (Thorlabs, HL6358MG) operating at 639 nm as excitation light source. For detection a CCD-camera (ANDOR IDUS 420) that was connected to a spectrograph (MS125), which in turn was fibre-coupled to an integrating sphere was used.

The prepared TMD MLs on the nanogap were loaded onto a piezoelectric transducer (PZT, P-611.3X, Physik Instrumente) for XY scanning. To obtain a high-quality wavefront of the excitation beam, a He–Ne laser (594.5 nm, <1.0 mW) was coupled and passed through a single-mode fiber (core diameter of ~3.5 μm) and collimated again using an aspheric lens. Finally, the beam was focused onto the sample using a microscope objective (NA = 0.8, LMPLFLN100X, Olympus). The PL responses were collected using the same microscope objective (backscattering geometry) and passed through an edge filter (FEL0550, Thorlabs) to remove the fundamental laser line. The PL signals were then dispersed onto a spectrometer (f = 328 mm, Kymera 328i, Andor) and imaged using a thermoelectrically cooled charge-coupled device (CCD, iDus 420, Andor) to acquire the PL spectra. Before the experiment, the spectrometer was calibrated using a mercury–argon lamp. A 150 g/mm grating blazed to 800 nm (spectral resolution of 0.62 nm) was used for PL measurements. Time-resolved PL measurements were performed with a time-correlated single-photon counting (TCSPC) method. A commercially available TCSPC module (PicoHarp, PicoQuant GmbH) was used to obtain the PL decay curves. A 405 nm picosecond laser diode with an 80 MHz repetition rate was used as an excitation source.