1. Monolayer WS2 epitaxially grown on (0001) sapphire substrates.
2. The size of each flake may be tuned in the range of 30-200 micrometers.
3 Density is tunable.
4. Single crystalline, highly luminescent.
5. Substrate: single-side polished C plane sapphire. Option of double-side polished sapphire available upon request.