183954.fig.002a
(a)
183954.fig.002b
(b)
183954.fig.002c
(c)
183954.fig.002d
(d)
Figure 2: (a) Transmittance spectra of VO2 films deposited at different O2-Ar ratios. Solid and dashed lines refer to low temperature (26°C) and high temperature (95°C), respectively. (b) Low temperature (M1 phase) absorptivity spectra. Thermal hysteresis loops of optical transmittance at photon energy of 0.83 eV and phase transition temperature are shown in (c) and (d).