High-spatial-resolution near-field photoluminescence and imaging of whispering-gallery modes in semiconductor microdisks with embedded quantum dots

III-nitride tunable cup-cavities supporting quasi whispering gallery modes from ultraviolet to infrared

“…We assume that the distribution of electromagnetic mode intensity in a WGM cavity, which is spatially inhomogeneous in principle, will control the local manifestation of the Purcell effect via either enhancement or inhibition of emission. Little attention was paid to this fact in the investigations of intensity distribution in the WGM cavities 18 19 .…”

Lasing of whispering-gallery modes in asymmetric waveguide GaInP micro-disks with InP quantum dots

“…The dot density (1-5 × 10 9 cm −2 ) and their sizes (∼100 nm) were estimated on uncapped samples using atomic force microscopy (AFM). The dot density of the waveguide structures was measured by near-field optical scanning microscopy [19]. The photoluminescence (PL) spectra of the InP QD ensemble shows a peak at 750 nm and half width of about 30 nm.…”

Lasing of whispering‐gallery modes in GaInP waveguide micro‐discs and rings with InP quantum dots

“…Observed thresholds are two orders of magnitude lower then for single InAs QD lasing in photonic crystal cavities [1]. We also report on the fabrication and study of micro-ring (MR) InP/GaInP QD cavities, which suppress high order radial WGMs and non-WGM low-Q modes of the MD [7].…”

“…The calculations of mode frequencies and field/intensity distributions, which allow the identification of mode polarization (TE or TM) and azimuthal (m) and radial (l) numbers, were done using 3D finite-differencetime-domain (FDTD) commercial software by Lumerical Inc. as was described in our previous work [7]. Figure 1a, b and c show a comparison of a scanning electron microscope (SEM) image of a micro-ring cavity (R=1.1 μm, W/R=5) with 2.2x2.2 μm-size NSOM images of the unprocessed InP/GaInP QD structure (b) and of a MD fabricated from it (R=2.2 μm), taken with spatial resolution ~150 nm (detection wavelength 730 nm).…”

“…High-spatial-resolution emission spectra were measured using near-field scanning optical microscopy (NSOM) [7] or using micro-PL through a metallic aperture formed on the initial InP/GaInP QD structure using EBL.…”