Structural characterization of WS2 flakes by Photoluminescence and ultra-low frequency Raman spectroscopy on a unique multimode platform

2D materials are best characterised using both Photoluminescence (PL) & ultra-low frequency Raman spectroscopy. PL is most appropriate for band structures characterisation at the micron scale.  Additionally, Raman analysis very close to the laser line, allowing a precise characterisation of the number of layers of 2D materials as specific interlayer vibration modes are excited in the ultra-low spectral Raman range (< 50ms-1). Click below as we explore the application of the two techniques using one of the 2D materials, WS2 flakes. 

​By definition, photoluminescence is the most appropriate technique for band structures characterisation at the micron scale. Indeed, the luminescence band of a semiconductor informs directly about the bandgap energy. 

Furthermore, the Raman analysis very close to the laser line allows a precise characterisation of the number of layers of a 2D material. Indeed, specific interlayer vibration modes are excited in this spectral range. Being able to have both spectroscopy techniques, photoluminescence and ultra-low frequency Raman on the same instrument is a vital feature to characterise these materials as much as possible. 
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