C- and L-band erbium-doped waveguide lasers with wafer-scale silicon nitride cavities

Abstract

We report on integrated erbium-doped waveguide lasers designed for silicon photonic systems. The distributed Bragg reflector laser cavities consist of silicon nitride waveguide and grating features defined by wafer-scale immersion lithography and a top erbium-doped aluminum oxide layer deposited as the final step in the fabrication process. The resulting inverted ridge waveguide yields high optical intensity overlap with the active medium for both the 0.98 μm pump (89%) and 1.5 μm laser (87%) wavelengths with a pump-laser intensity overlap of >93%. We obtain output powers of up to 5 mW and show lasing at widely spaced wavelengths within both the C and L bands of the erbium gain spectrum (1536, 1561, and 1596 nm).

Superconducting Optoelectronic Circuits for Neuromorphic Computing

“…Much work in this area was motivated by the prospect of room-temperature light sources [68] for CMOS and telecommunications [69], and in particular room temperature lasers. This includes various point defects in Si including Er [70][71][72][73] and other emissive centers giving rise to electric-dipole-mediated transitions [67,[74][75][76][77][78][79][80][81][82], as well as band-edge or Si nanocrystal-based emission processes [83][84][85]. While the efficiencies of many of these emitters fall off exponentially with increasing temperature, the SNSPDs required for this application operate at cryogenic temperatures where many point defects have suitable efficiencies.…”

Integrated rare-Earth doped mode-locked lasers on a CMOS platform

“…Energy transfer upconversion (ETU, see dotted and dashed arrows in Fig.1) can have a deterimental impact on gain, depleting the excited-state laser level and inhibiting population inversion. The impact of these processes in erbium-doped aluminum oxide has been characterized in detail in [9]. In highly-doped thulium fiber lasers and channel waveguides, the cross-relaxation (CR, see dashed arrows in Fig.1) effect has been shown to increase the slope efficiency above 70% [14], [15].…”

“…III-V gain materials can be brought to bear on a silicon photonics platform via heterogeneous integration [6]. Due to the success of the recently demonstrated planar waveguide lasers utilizing rareearth doped materials as the gain medium [7], [8] and its co-integration on a silicon-photonics platform through postprocessing that involves only single-step deposition of the gain medium on the otherwise completely prefabricated and processed electronic-photonic wafer [9][10][11][12], the mode-locked lasers based on rare-earth doped gain media become possible. The advantage is that the gain waveguide is comprised of a glass material where two-photon absorption occurs at much higher peak-intensities compared to III-V materials, and, therefore shorter and more energetic pulses can be directly generated from the mode-locked laser.…”

Sideband pump-probe technique resolves nonlinear modulation response of PbS/CdS quantum dots on a silicon nitride waveguide

“…[30][31][32] Additionally, a range of hybrid photonic devices based on silicon nitride structures has been demonstrated. 10,[33][34][35][36][37] In contrast to pure silicon, the material does not display large intrinsic nonlinearities or a substantial free carrier absorption 38 and therefore allows us to observe the nonlinear response of the QDs without waveguide-induced background. A schematic of the sample is displayed in Fig.…”