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In this paper, we demonstrate a novel structure for 850- and 940-nm wavelength high-speed vertical-cavity surface-emitting lasers (VCSELs). Extra shallow apertures (~20 nm) are etched on the topmost current spreading (CS) layer of 850- or 940-nm VCSELs, which have Zn-diffusion and oxide-relief apertures inside. Such a structure simultaneously allows a significant enhancement of the output power and a reduction in the number of optical modes in the optical spectrum, which migrates toward the quasi-single-mode (QSM). Comparison is made to multi-mode (MM) reference VCSELs produced without etching of the CS layer. The etched devices exhibit a larger signal-to-noise ratio for error-free 32 Gbit/s transmission over 100-m MM fibers (MMFs) at both wavelengths (850 and 940 nm). In addition, the dynamic/static performance of the etched samples is also superior to that of a QSM reference sample, produced by utilizing only Zn-diffusion apertures without etching of the CS layer. The demonstrated device structure opens the door to greatly improve the performance of SM and high-power VCSELs for high-speed data transmission.

We demonstrate Zn-diffusion 940 nm VCSELs, which exhibits high-power (6.8 mW), highly single-mode (SMSR>50 dB) performances over the full range of bias currents. A wide −3-dB E-O bandwidth (18 GHz) and a short rise/fall time (20/11 ps) can also be achieved simultaneously.

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We demonstrate 940nm VCSELs with record-high 3-dB E-O bandwidths as 40 (32) GHz under room-temperature (85°C) operation. It achieves error-free 60Gbps (room-temperature) and 50Gbps (85°C) OOK transmission over 1m and 100m OM5 fiber, respectively.

By creating shallow surface relief patterns above the Zn-diffusion apertures of VCSELs, a significant reduction in optical linewidth, enhancement in output power, and improvement in high-speed transmission performance over multi-mode fiber (MMF) have been first demonstrated.

850nm SM-VCSELs can suffer from low power particularly at high temperatures, as compared to their MM counterparts. We demonstrate stable 850nm and 910nm SM-VCSELs at 85°C under moderate current densities, capable of unequalized 25Gb/s NRZ transmission over 1 km Wideband-MMF and beyond.

We demonstrate 940-nm vertical-cavity surface-emitting lasers (VCSELs) with record-high −3 dB electrical-to-optical bandwidths of 40 and 32 GHz under room-temperature and 85 °C operations, respectively. The combination of Zn-diffusion with oxide-relief apertures inside the VCSEL cavity structure can greatly reduce the differential resistance and parasitic capacitance, which leads to an enhancement in the resistance-capacitance (RC)-limited bandwidth. Devices with different sizes of oxide-relief apertures are analyzed by use of the measured S 21 and S 11 two-port scattering parameters and equivalent circuit modeling techniques. For a device with a 3-μm diameter oxide-relief aperture, the extracted intrinsic bandwidth can be as high as 46.3 GHz. By using this novel device as the transmitter, we can achieve 60 Gbps error-free [bit-error-ratio (BER) on – off keying transmission over a 1-m OM5 fiber under room temperature (RT) operation, without using any signal processing. In addition, invariant 50-Gbps transmission performance from RT to 85 °C operations, over a 100-m OM5 fiber has also been successfully demonstrated (with a BER < 1 × 10−7).