Tu plan fluor100

1T-TaS₂ crystals and natural graphite
were mechanically exfoliated using adhesive tape (80 μm thick
adhesive plastic film from Ultron Systems) inside an argon glovebox.
The exfoliated samples were inspected primarily by optical microscopy
(Nikon Eclipse LV-100 optical microscope with a Nikon TU Plan Fluor
100× objective lens of 1 mm working distance and a numerical
aperture of 0.9 and 10 nm fwhm visible band-pass filters from Thorlabs)
as a fast tool for the identification of thin-layers and atomic force
microscopy (Nano-Observer AFM from CSI Instruments) inside an argon
glovebox. Following the recently developed fabrication of vertical
vdWHs for studying air unstable 2D magnets, like CrI₃ or
MnPS₃,^{47 (link),61 (link)} the vertical vdWHs were built
in a deterministic way using polycarbonate, as reported in reference^{46 (link)} and placed on top of prelithographed metal contacts
fabricated by conventional electron beam lithography techniques (5
nm Ti/50 nm Pd) on 285 nm SiO₂/Si substrates (from NOVA
Electronic Materials, LLC).

A confocal laser scanning fluorescence microscope (A1⁺ system, Nikon) was used to obtain confocal PFOM images of polydomain sample at 25 °C (nematic) with the higher 3D optical resolutions. An optically pumped semiconductor laser (LU-N4 Laser Unit, Nikon, equipped with Sapphire 488, Coherent Inc.) was used to excite the fluorescent probes at 488 nm and the emitted light between 525 and 595 nm was collected. An objective lens with an NA of 0.90 (TU PlanFluor100 ×, Nikon) was used. The confocal PFOM images were acquired at the voxel size of typically 30(x) × 30(y) × 50(z) nm³. The excitation laser was linearly polarised and emitted fluorescence in the same polarisation was collected using a polariser. The obtained images were properly deconvoluted using the associated software. In the present LCEs with dyes, image slices from the top surface to a few µm depth were properly taken with sufficient fluorescent intensity.