GaAs-AlGaAs core-shell nanowire lasers on silicon: invited review

• Published in: Semiconductor science and technology Vol. 32; no. 5; pp. 53001 - 53022
• Main Authors: Koblmüller, Gregor, Mayer, Benedikt, Stettner, Thomas, Abstreiter, Gerhard, Finley, Jonathan J
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.05.2017
• Subjects: III-V semiconductor nanowires; monolithic integration on Si; nanolasers; optical pumping; ultrafast gain dynamics
• ISSN: 0268-1242; 1361-6641
• DOI: 10.1088/1361-6641/aa5e45

Semiconductor nanowire (NW) lasers provide significant potential to create a new generation of lasers and on-chip coherent light sources by virtue of their ability to operate as single mode optical waveguides at the nanoscale. Due to their unique geometry, a major benefit lies also in the feasibility for direct integration on silicon (Si), enabling III-V-on-Si NW lasers that could fuel applications in optical interconnects and data communication. In this review, we describe the state-of-the-art and recent progress in GaAs-AlGaAs based NW lasers emitting in the near infrared (NIR) spectral region, with a specific emphasis on integration on a Si platform. First, we explore design rules for the photonic properties in GaAs NW waveguides based on finite difference time domain calculations. The lasing characteristics of GaAs-AlGaAs core-shell NW lasers are then investigated under various different optical pumping schemes ranging from pulsed to continuous wave excitation. We further review recent activities on the realization of low-dimensional quantum heterostructures inside NW cavities as a means to tune lasing wavelength, gain and threshold properties. Ultimately, we describe schemes for monolithic integration of GaAs-based NW lasers directly on Si and show how such vertical nanocavity lasers are excellent candidates for low-threshold lasing, high spontaneous emission coupling (high β-factor lasers), and ultrafast emission characteristics.