Premium
Electrically Pumped Epitaxially Regrown GaSb‐Based Type‐I Quantum‐Well Surface‐Emitting Lasers with Buried High‐Index‐Contrast Photonic Crystal Layer
Author(s) -
Shterengas Leon,
Liu Ruiyan,
Kipshidze Gela,
Stein Aaron,
Lee Won Jae,
Hosoda Takashi,
Zakharov Dmitri N.,
Kisslinger Kim,
Belenky Gregory
Publication year - 2022
Publication title -
physica status solidi (rrl) – rapid research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.786
H-Index - 68
eISSN - 1862-6270
pISSN - 1862-6254
DOI - 10.1002/pssr.202100425
Subject(s) - materials science , optoelectronics , photonic crystal , lasing threshold , heterojunction , laser , cladding (metalworking) , optics , diode , refractive index contrast , epitaxy , semiconductor laser theory , band gap , quantum well , molecular beam epitaxy , layer (electronics) , nanotechnology , fabrication , wavelength , medicine , physics , alternative medicine , pathology , metallurgy
Epitaxially regrown electrically pumped photonic crystal surface‐emitting lasers (PCSELs) emitting near 2 and 2.6 μm are designed, fabricated, and characterized. A high‐index‐contrast photonic crystal layer is incorporated into the GaSb‐based laser heterostructure by air‐hole‐retaining epitaxial regrowth. A square lattice of triangular holes is etched in the top waveguide core layer of the incomplete laser heterostructure. The nanopatterned surface is subsequently cleaned and regrown with AlGaAsSb p‐cladding material. Transmission electron microscopy studies demonstrate uniform regrowth over the nanopatterned GaSb surface. The selected regrowth regimes yield a buried 2D array of elongated air‐holes. The diode PCSELs based on moderately etched nanopatterns demonstrate band‐edge lasing near 2 μm up to room temperatures. The cascade diode PCSELs operate near 2.6 μm with minimum threshold current densities of about 500 A cm −2 achieved at 180 K. The devices generate mW level output in narrow divergence beam emitted from the window in substrate contact. The angle‐resolved electroluminescence measurements reveal a four‐sub‐band band structure with an apparent photonic bandgap corresponding to the buried high‐index‐contrast square photonic crystal layer. The PCSELs made of heterostructures supporting two modes in the vertical direction demonstrate two sets of sub‐bands showing anti‐crossing‐like interaction.