Demonstration of post-growth wavelength control of VCSELs using high-contrast gratings

• We demonstrate post-growth wavelength setting of vertical-cavity surface-emitting lasers (VCSELs) using high-contrast gratings (HCGs). By fabricating HCGs with different duty-cycle and period, the HCG reflection phase can be varied, in effect giving different optical cavity lengths for HCGVCSELs with different grating parameters. This enables fabrication of monolithic multi-wavelength HCG-VCSEL arrays for wavelength-division multiplexing (WDM). The GaAs HCG is suspended in air by selective removal of an InGaP sacrificial layer. Electrically injected 980-nm HCGVCSELs with sub-mA threshold currents indicate high reflectivity from the GaAs HCGs. Lasing over a wavelength span of 15 nm was achieved, enabling a 4-channel WDM array with 5 nm channel spacing. Device design, fabrication and experimental proof-of-concept are presented.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Annan elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Other Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

Semiconducting gallium

VCSELs

Optical interconnects

Diffraction gratings

High contrast grating

Gallium arsenide

CWDM

Wavelength control

Wavelength division multiplexing

Sacrificial layer

Threshold currents

High-contrast gratings

Optical waveguides

High reflectivity

Transceivers

Electrically injected

Surface emitting lasers

Publication and Content Type

art (subject category)

ref (subject category)