Oxide-Confined VCSELs

The first electrically pumped VCSEL was demonstrated with metal cavities by Iga (1979); however, the threshold current was too high for laser applications. Distributed Bragg reflector (DBR) cavities proposed by Scifres and Burnham (1975) were then adopted for VCSEL to improve the optical cavity loss. Yet, it was not use until the important discovery of the native oxide of AlGaAs by Holonyak and Dallesasse (1990) to provide simultaneous current and optical confinement in semiconductor laser. Subsequently, the first oxide-confined VCSEL with “low threshold” was demonstrated by Deppe (1994). The reliable oxide-confined VCSELs have made into a practical use (2000) for short-range Gigabit energy-efficient optical links and high- performance computer due to the growing demand of faster access to large amounts of information and have revolutionized our daily life from data centers to 3D sensing applications. Today, the oxide-confined VCSELs have advanced error-free data transmission (BER $\leq$ 10 -12 ) up to 57 Gb/s at 25 $\circ$C and 50 Gb/s at 85 $\circ$C, and demonstrated the pre-leveled 16-QAM OFDM data at 104 Gbit/s under back-to- back transmission with the received EVM, SNR, and BER of 17.3\%, 15.2 dB, and 3.8x10$^{-3}$ , respectively.