Thermally tunable silicon photonic microdisk resonator with transparent graphene nanoheaters

Abstract

Thermally-tuning silicon micro-cavities are versatile and beneficial elements in low-cost large-scale photonic integrated circuits (PICs). Traditional metal heaters used for thermal tuning in silicon micro-cavities usually need a thick SiO 2 upper-cladding layer, which will introduce some disadvantages including low response speed, low heating efficiency, low achievable temperature and complicated fabrication processes. In this paper, we propose and experimentally demonstrate thermally-tuning silicon micro-disk resonators by introducing graphene transparent nano-heaters, which contacts the silicon core directly without any isolator layer. This makes the graphene transparent nano-heater potentially to have excellent performances in terms of the heating efficiency, the temporal response and the achievable temperature. It is also shown that the graphene nano-heater is convenient to be used in ultrasmall photonic integrated devices due to the single-atom thickness and excellent flexibility of graphene. Both experiments and simulations imply that the present graphene transparent nano-heater is promising for thermally-tuning nanophotonic integrated devices for e.g. optical modulating, optical filtering/switching, etc.

Chalcogenide glass-on-graphene photonics

“…4d). The responsivity figure is on par with, or in some cases superior to, state-of-the-art waveguide-integrated graphene detectors operating in the mid-IR 40 and near-IR 9,11,39,41 . Hall measurements indicate that the Fermi level of graphene used in the device is located at 0.34 eV below the Dirac point owing to substrate doping 42 .…”

Emerging material systems for integrated optical Kerr frequency combs

“…In whispering gallery mode microcavities, the two most commonly used approaches for changing or modulating the refractive index are the thermo-optic effect and the electro-optic (EO) effect (Pockels effect) [144,[163][164][165][166][167][168][169][170][171][172][173][174][175][176]; however, other mechanisms like pressure (or acoustics wave-induced compression) have been used to a lesser extent. [53,177,178] In most materials used in integrated optics, the thermo-optic effect is orders of magnitude slower in response than the electro-optic effect ( Fig.…”

Highly Efficient Silicon Photonic Microheater Based on Black Arsenic–Phosphorus

“…This value is much higher than the TiN heater, which has been widely used in silicon photonics . It is also quite comparable with the reported graphene heater with cavity or slow light enhancement . This suggests that the b‐AsP heater can potentially eliminate the need of several hundreds of micrometers long waveguide or narrowband resonator for heater.…”

“…The thermal conductivities are defined to be ≈100 W m −1 K −1 , ≈80 W m −1 K −1 , and ≈1.4 W m −1 K −1 for b‐AsP flake, silicon, and the buried oxide, respectively. The heat convection coefficient of air is set to ≈5 W m −2 K −1 , and the room temperature (RT) is 298.15 K. As shown in Figure a, the highest temperature occurs at the b‐AsP sheet suspended on the air gap. Though the temperature in the waveguide region is slightly lower, there is still much heat localized at the waveguide center, which can be seen more clearly in the cross‐sectional and top‐view heat distribution images as shown in Figure b,c.…”