Pressure engineering of van der Waals compound RhI3: bandgap narrowing, metallization, and remarkable enhancement of photoelectric activity

Stacking Faults Enabled Second Harmonic Generation in Centrosymmetric van der Waals RhI3

“…45 Based on this phenomenon, 2L AC̅ RhI 3 with the interlayer distance decreased by 2.5% and 5% are used to simulate the system under low pressure (below 3 GPa). 46 SHG spectra with and without pressure corresponding to |χ yyy (2) |, |χ yxx (2) |, and |χ xxy (2) | with and without the compression of interlayer distance are shown in Figures 6a and S17, respectively. It is found that there is an overall enhancement in SHG intensity when the interlayer distance is shortened, which agrees well with the experimental measurements under pressure below 3 GPa with incident lasers at 810 and 1064 nm.…”

“…Because vdW RhI 3 nanoflakes are primarily adsorbed on the surface of diamond anvil during high-pressure experiments, the external pressure is mainly out-of-plane and would result in obvious compression of interlayer spaces . Based on this phenomenon, 2L AC̅ RhI 3 with the interlayer distance decreased by 2.5% and 5% are used to simulate the system under low pressure (below 3 GPa) . SHG spectra with and without pressure corresponding to |χ yyy (2) |, |χ yxx (2) |, and |χ xxy (2) | with and without the compression of interlayer distance are shown in Figures a and S17, respectively.…”