Broadband wavelength-tunable enhanced light emission based on graphene MEMS

The modulation of light emission in a composite structure of a graphene microelectromechanical system (MEMS) and a photonic crystal microcavity is investigated theoretically. By suspending photonic crystal structures on graphene ribbons and applying a driving voltage to control the cavity length of the microcavity, the radiation intensity of light at different wavelengths can be enhanced, while the radiation intensity of light at other wavelengths can be suppressed. The numerical results show that the device has a tunable wavelength range greater than 200 nm or a tunable frequency range greater than 200 THz, which is an order of magnitude larger than traditional wavelength-tunable MEMS devices. Additionally, the device's size can be reduced by over an order of magnitude. Notably, this tuning range covers almost all color ranges, making it applicable to color displays. The structure indicates that this modulator can achieve full-color displays within a single pixel, with a color gamut range reaching 186% of the Adobe RGB color gamut. The device is small in size and will have important applications in fields such as frequency-tunable optical communication, laser radar, augmented reality technology, and wearable display devices.