Optically tunable guide-mode resonance grating based on VO2 phase transition material

•In this paper, the optimal optical transmission and tuning can be achieved by optimizing the device structure.•Based on the large insulator-to-metal transition (IMT) characteristic tuned by thermally driven of VO2 in the near-infrared range, we show that a full width at half maximum (FWHM) of about 100 nm of the transmittance resonance spectra of the dielectric GMR in VO2 grating offers remarkable extinction modulation depths (68%) at 1535 nm for tunability.•The tunability is accompanied by a hysteresis-like behavior that can be exploited for versatile memory effects.•In addition, we experimentally demonstrate tuning of the reflection phase over 20°.•This work further improves the research topic of GMR and expands the design of novel reconfigurable devices for photonics.