Figure 5.

Phonon dynamics under high pressure. a,b) Raman spectra of monolayer 2H‐MoS₂ and 1T′ MoS₂ under the indicated pressure. It shows the pressure‐dependent phonon dynamics of different‐phase MoS₂ monolayer. c) FWHM evolutions as a function of pressure from BP. The vertical dashed lines represent the pressure points of the structural phase transitions. d) FWHM evolutions of BP under pressure ranging from 0 to 4 GPa. e) Raman spectra of 2D perovskite (PEA)₂PbI₄ under the indicated pressure. f) Raman peak position evolution of Peak 1 during the compression and decompression. a,b) Reproduced with permission.^{[ 18 ]} Copyright 2014, American Chemical Society. c,d) Reproduced with permission.^{[ 33 ]} Copyright 2017, American Physical Society. e,f) Reproduced with permission.^{[ 39 ]} Copyright 2017, American Association for the Advancement of Science.