Figure 1

(a) Change of transmissions measured at 27 and $68°\mathrm{C}$ at a pump power of 100 mW. The negative delay data ($A$), change of $\Delta T/T$ (rate of transmission change) near zero delay ($B$), incoherent part ($C$). (b) The temperature dependence of coherent phonon oscillations measured at a pump power of 100 mW. The peaks near zero delay were removed. (c) The temperature dependence of the fast Fourier transformed (FFT) spectra taken from the coherent phonon oscillations in (b). The peaks at 4.5 and 6 THz appear simultaneously. (d) The temperature dependence of the sum of the monoclinic $A_g$ peak spectral intensities measured at pump powers of 30 and 100 mW. (e) The temperature dependence of FFT spectra of coherent phonon oscillations measured in the forward and backward directions at 30 mW pump power near $T_{\mathrm{SPT}}$.Reuse & Permissions

Figure 2

(a) The temperature dependence of the resistance simultaneously measured by x-ray diffraction. The inset cited from Ref. [6] shows the temperature dependence of carriers near the MIT. The red (gray) solid circles indicate holes. (b) The temperature dependence of the XRD data.Reuse & Permissions