In this work, we present on optical gain and lasing in an ultra-compact thulium-silicon hybrid microdisk resonator emits around 1.9 µm with an internal slope efficiency of 60% and > 1 mW on-chip output power.

Silicon photonics is an ideal platform for low-cost, energy-efficient, and high-performance optical microsystems. However, because silicon is an inefficient light emitting material, the development of simple, inexpensive, and scalable monolithic amplifiers and light sources has been a significant challenge. Here, optical gain and lasing in an ultra-compact hybrid rare-earth silicon microdisk resonator are reported. The microdisk design is straightforward and compatible with the fabrication steps and device dimensions available in all silicon photonics foundries, while the thulium-doped tellurite gain medium is added in a low-temperature single-step sputter deposition. This approach allows for low-cost and high-volume wafer-scale manufacturing and co-integration of rare-earth amplifiers and light sources with silicon passive and active devices with no adjustment to standard process flows. The hybrid laser is pumped at standard telecom wavelengths around 1.6 µm and exhibits stable single-mode emission at 1.9 µm, with an internal slope efficiency of 60% and >1 mW on-chip output power. The laser is highly promising for emerging communications and sensing applications and opens new possibilities for the development of monolithic rare-earth optical amplifiers and lasers directly on silicon.

Subwavelength grating (SWG) metamaterial waveguides and ring resonators on a silicon nitride platform are proposed and demonstrated. The SWG waveguide is engineered such that a large overlap of 53% of the Bloch mode with the top cladding material is achieved, demonstrating excellent potential for applications in evanescent field sensing and light amplification. The devices, which have critical dimensions greater than 100 nm, are fabricated using a commercial rapid turn-around silicon nitride prototyping foundry process using electron beam lithography. Experimental characterization of the fabricated device reveals excellent ring resonator internal quality factor (2.11 × 10 5 ) and low propagation loss (≈1.5 dB cm −1 ) in the C-band, a significant improvement of both parameters compared to silicon-based SWG ring resonators. These results demonstrate the promising prospects of SWG metamaterial structures for silicon nitride based photonic integrated circuits. IntroductionSilicon photonics (SiP) has become a leading integrated photonics technology by leveraging existing microelectronics manufacturing processes and infrastructure to produce compact, scalable,

We report on the design, fabrication and characterization of subwavelength grating metamaterial waveguides coated with tellurium oxide. The structures are first fabricated using a standard CMOS compatible process on a silicon-on-insulator platform. Amorphous tellurium oxide top cladding material is then deposited via post-process RF magnetron sputtering. The photonic bandstructure is controlled by adjustment of the device geometry, opening a wide range of operating regimes, including subwavelength propagation, slow light and the photonic bandgap, for various wavelength bands within the 1550 nm telecommunications window. Propagation loss of 1.0 ± 0.1 dB/mm is reported for the tellurium oxide-cladded device, compared to 1.5 ± 0.1 dB/mm propagation loss reported for the silicon dioxide-cladded reference structure. This is the first time that a high-index (n > 2) oxide cladding has been demonstrated for subwavelength grating metamaterial waveguides, thus introducing a new material platform for on-chip integrated optics.

No abstract