Impurity-induced disordering (IID) in vertical-cavity surface-emitting lasers (VCSELs) has been shown to provide enhanced performance, such as achieving single fundamental-mode operation with higher output powers when compared to conventional VCSELs. This work presents the performance of oxide-confined, λ ~ 850 nm, VCSELs fabricated with varying IID aperture sizes which are characterized for maximum single-fundamental-mode output power. The electrical and optical performance of these devices are shown in comparison to traditional oxide-confined VCSELs and the optimal IID aperture size is experimentally validated. Control of the lateral-to-vertical (L/V) IID aperture profile is then demonstrated through engineering the strain induced by the IID diffusion mask. This extensive control over the IID aperture enables improved, manufacturable, IID VCSEL designs.
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Oxide-Confined VCSELs for High-Speed Optical Interconnects
The electrically pumped vertical-cavity surface- emitting laser (VCSEL) was first demonstrated with metal cavities by Iga (1979); however, the device threshold current was too high. Distributed Bragg reflector cavities proposed by Scifres and Burnham (1975) were adopted to improve the optical cavity loss. Yet, it was not a practical use until the discovery of the native oxide of AlGaAs and the insertion of quantum wells to provide simultaneous current and optical confinement in semiconductor laser by Holonyak and Dallesasse (1990). Later, the first “low- threshold” oxide-confined VCSEL was realized by Deppe (1994) and opened the door of commercial application for a gigabit energy-efficient optical links. At present, we demonstrated that the oxide-confined VCSELs have advanced error-free data trans- mission [bit-error rate (BER) ≤ 10−12]to 57 Gb/s at 25 °C and 50 Gb/s at 85 °C, and also demonstrated that the pre-leveled 16-quadrature amplitude modulation orthogonal frequency- division multiplexing data were achieved at 104 Gbit/s under back-to-back transmission with the received error vector mag- nitude, SNR, and BER of 17.3%, 15.2 dB, and 3.8 × 10−3, respectively.
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- Award ID(s):
- 1640196
- NSF-PAR ID:
- 10064923
- Date Published:
- Journal Name:
- IEEE journal of quantum electronics
- Volume:
- 54
- Issue:
- 3
- ISSN:
- 1558-1713
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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