The application of strain into GeSn alloys can effectively modulate the band structures, thus creating novel electronic and photonic devices. Raman spectroscopy is a powerful tool for characterizing strain; however, lack coefficient makes it difficult accurate determination in alloys. Here, we have investigated Raman-strain function Ge1-xSnxalong ?1 0 0? 1 directions. nanomembranes (NMs) with d...