| Summary: | Vanadium dioxide (VO<sub>2</sub>) has emerged as a prominent optical phase change material (O-PCM) for creating high performance devices based on hybrid silicon platforms. However, realizing an efficient and compact optical modulator required for Mach-Zehnder interferometer (MZI) structures, still remains a major challenge in active Si-platforms enabled by VO<sub>2</sub>. This is mainly due to the simultaneous variation of both real and imaginary parts of the refractive index during the phase transition process, which is a significant issue. A modified MZI structure is proposed in this paper while the refractive index variation issue is overcome by operating in the wavelength range between 1.5 to <inline-formula> <tex-math notation="LaTeX">$1.6~\mu \text{m}$ </tex-math></inline-formula> including the optical C-band. An indium tin oxide (ITO) layer is considered as the microheater for the thermal excitation. An optimized triggering signal with an amplitude of 12.5 V along with an arm length of <inline-formula> <tex-math notation="LaTeX">$2.35~\mu \text{m}$ </tex-math></inline-formula> of the MZI device (<inline-formula> <tex-math notation="LaTeX">$V_{\pi }L_{\pi }= 30 \,\,\text {V}\cdot \mu \text{m}$ </tex-math></inline-formula>) established a <inline-formula> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula>-shift at the output of the device. The proposed device has ER >35 dB at the entire optical C-band and consumes <inline-formula> <tex-math notation="LaTeX">$\sim 26$ </tex-math></inline-formula> pJ for modulating a single bit with a delay of 3.5 ns.
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