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Surface–trapped electromagnetic waves can be localized at a boundary between a semiconductor distributed Bragg reflector (DBR) and a homogeneous dielectric medium or air. These waves enable a novel class of both in–plane–emitting and vertically–emitting optical devices including edge–emitting lasers, disk microlasers, near–field fiber–coupled lasers as well as vertical cavity surface emitting lasers (VCSELs). We show that the surface–trapped modes can be controlled by tuning the thickness of a single DBR layer. Diagrams in variables “wavelength – thickness of the control layer” are constructed for both TM and TE optical modes revealing the parameter domains, in which surface–trapped modes exist. The domains contain cusps, in the vicinity of which surface–trapped modes are allowed only in a narrow spectral region, enabling wavelength–stabilized operation of a laser. For an edge–emitting structure designed for lasing at ~1 μm, the lasing wavelength shifts upon temperature at a rate ~0.07 nm/K. The fraction of the optical power of the surface–trapped mode accumulated in the air can reach ~60%. In oxide–confined VCSEL structures the surface–trapped mode can be used for engineering of the interaction with the VCSEL lasing modes. Deposition of an effective (3λ/4)–thick additional layer on top of the top DBR of the VCSEL allows surface–trapped modes to reach the wavelength of the VCSEL lasing modes. Interaction of these two types of generally non–orthogonal optical modes results in the lateral leakage of the VCSEL emission. Mapping of the VCSEL wafers in areas with the variable aperture diameters D shows non–monotonous behavior of side mode suppression ratio (SMRS) versus D oscillating in the range from 7 dB to ~30 dB with three clearly revealed maxima in the SMSR at particular aperture diameters varied in the range from ~3 μm to ~5 μm. Similar oscillatory behavior was previously predicted for a different type of leaky VCSELs. VCSELs with SMSR above 20 dB are tested for data transmission over a multimode fiber (MMF). 40Gb/s open eye data transmission over 1.4 km OM5 MMF without pre–emphasis or equalization is demonstrated is such device.
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