Praevium Research delivers three talks at Photonics West 2020

Tunable room-temperature continuous-wave mid-infrared VCSELs

V. Jayaraman, B. Kolasa, et al.

During the last two years, our group has demonstrated the first room temperature continuous wave (RTCW) fixed wavelength VCSELs operating above 3 microns, in both optically pumped and electrically pumped devices. Our devices employ wafer bonding of GaSb-based active regions with GaAs-based mirrors. In this paper, we describe recent progress on tunable devices. These include CW optically pumped devices with >5nm of tuning near 3.3um using variation of pump power, and CW electrically pumped devices with >3nm tuning near 3.3um using variation of bias current, for methane sensing. We will also show recent progress on MEMS-tunable mid-IR VCSELs.

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Widely tunable electrically pumped 1050nm MEMS-VCSELs for optical coherence tomography

V. Jayaraman, Christopher Burgner, et al.

In recent years, MEMS-tunable VCSELs at 1050/1310nm have emerged as a leading swept source for optical coherence tomography imaging. Optically pumped 1050nm MEMS-VCSELs (MEMS-oVCSELs) have previously achieved >100nm tuning range, but electrically pumped MEMS-VCSELs (MEMS-eVCSELs) have lagged behind. In this work, we demonstrate 97nm continuous tuning range in a MEMS-eVCSEL operating near 1050nm, and 100nm total tuning range, representing the widest tuning ranges achieved to date, and rivaling the performance of optically pumped devices. Our devices employ a strain-compensated InGaAs/GaAsP gain region, a wideband fully oxidized GaAs/AlxOy back mirror, and 3 electrical contacts for current injection and MEMS actuation.

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Reliable widely tunable electrically pumped 1050nm MEMS-VCSELs with amplifier in single butterfly co-package

Christopher Burgner, John Carter, et al.

MEMS-tunable VCSELs at 1050nm have emerged as a high performance swept source for ophthalmic optical coherence tomography. Prior optically pumped MEMS-VCSELs exhibited over 100nm of tuning range but required pump lasers and external amplifiers which increased cost. In this work, we demonstrate the first electrically pumped 1050nm MEMS-eVCSEL co-packaged with a wideband amplifier to achieve over 70nm tuning at over 30mW of output power. Ophthalmic images acquired at A-scan rates of 800kHz showcase the simplicity of our single telecom grade 14pin butterfly co-package. Our wideband fully oxidized GaAs/AlxOy back mirror provides extensibility to ~100nm eVCSEL tuning, and ~20000 hour reliability.