Figure 2

Angle-resolved polarized Raman spectra and the corresponding contour maps of the 129-nm thick GeAs flake acquired in (a) parallel and (b) perpendicular configurations. (c–f) Polar plots of the Raman intensities of \(A_{g}^{3} \left( {147\;{\text{cm}}^{ - 1} } \right)\), \(A_{g}^{4} \left( {174\;{\text{cm}}^{ - 1} } \right)\), \(A_{g}^{6} \left( {276\;{\text{cm}}^{ - 1} } \right)\) and \(B_{g}^{1} \left( {257\;{\text{cm}}^{ - 1} } \right)\) modes in parallel configuration for the 129-nm thick GeAs flake. (g–j) Polar plots for \(A_{g}^{2} \left( {105\;{\text{cm}}^{ - 1} } \right)\), \(A_{g}^{3} \left( {147\;{\text{cm}}^{ - 1} } \right)\), \(A_{g}^{6} \left( {276\;{\text{cm}}^{ - 1} } \right)\) and \(B_{g}^{1} \left( {257\;{\text{cm}}^{ - 1} } \right)\) modes in perpendicular configuration for the 129-nm thick GeAs flake. (k–n) Polar plots for \(A_{g}^{3}\), \(A_{g}^{4}\), \(A_{g}^{6}\) and \(B_{g}^{1}\) modes in parallel configuration for the 11 nm-thick GeAs flake. Blue dots are the experimental data and red solid curves are the fitted data with Eq. (1)–(4).