Ultrafast Zn-Diffusion and Oxide-Relief 940 nm Vertical-Cavity Surface-Emitting Lasers Under High-Temperature Operation

• Published in: IEEE journal of selected topics in quantum electronics Vol. 25; no. 6; pp. 1 - 7
• Main Authors: Cheng, Chen-Lung, Ledentsov, Nikolay, Khan, Zuhaib, Yen, Jia-Liang, Ledentsov, Nikolay N., Shi, Jin-Wei
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.11.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Apertures; Bandwidth; Bandwidths; Capacitance; Current measurement; Equivalent circuits; Frequency measurement; High temperature; On-Off Keying; Semiconductor lasers; Signal processing; Temperature measurement; Vertical cavity surface emission lasers; Vertical cavity surface emitting lasers; vertical-cavity surface emitting lasers (VCSEL); Wavelength measurement
• ISSN: 1077-260X; 1558-4542
• DOI: 10.1109/JSTQE.2019.2921385

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) <;1 × 10 -12 ] 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 ).