Room-Temperature Continuous-Wave Electrically Pumped 3.3 Micron Vertical Cavity Laser

Successful development of vertical cavity surface emitting lasers (VCSELs) in the mid-infrared wavelength range from 3-5um promises low-cost detection of fundamental vibrational absorption lines of numerous environmentally and industrially important gases, such as methane, ethane, nitrous oxide, and carbon dioxide. Thus far, however, realization of room temperature continuous wave (RTCW) VCSELs in this wavelength region has remained an elusive goal. Prior workers have reported pulsed operation at 3.3um above room temperature using an interband cascade laser active region
¹
, and CW operation up to -7C using type II quantum wells in a type II non-cascaded multi-quantum well configuration
²
. Our group reported the first optically pumped room RTCW VCSELs operating at 3.35um in February 2018
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. In this paper, we report what is to our knowledge the first demonstration of electrically pumped RTCW VCSEL operation at >3 micron wavelength.