Fig. 5: Raman spectroscopy studies of MoS₂ MLs implanted with Se ions at 20 eV with different fluences.

a Room temperature Raman spectra of MoS₂ MLs implanted at four different fluences. The spectra are normalized to the Si signal at 520 cm⁻¹ (not shown) and offset vertically for clarity. b Change of intensities of A′ Raman lines with ion beam fluence. Peak areas are obtained by fitting with Voigt profiles with Origin (OriginLab). Error bars are associated standard error from the fitting routine. The blue curve with the axis on the right shows the ratio between the out of-plane-vibration of S–Mo–Se bonds, \(A_{{\mathrm{MoSSe}}}^\prime\), to that of the pristine S–Mo–S bonds, A′.