Mesa-top quantum dot single photon emitter arrays: Growth, optical characteristics, and the simulated optical response of integrated dielectric nanoantenna-waveguide systems

Abstract

Nanophotonic quantum information processing systems require spatially ordered, spectrally uniform single photon sources (SPSs) integrated on-chip with co-designed light manipulating elements providing emission rate enhancement, emitted photon guidance, and lossless propagation. Towards this goal, we consider systems comprising an SPS array with each SPS coupled to a dielectric building block (DBB) based multifunctional light manipulation unit (LMU). For the SPS array, we report triggered single photon emission from GaAs (001)

Planarized spatially-regular arrays of spectrally uniform single quantum dots as on-chip single photon sources for quantum optical circuits

“…Figure 1, panel (a) shows a SEM image of part of a 5×8 array of pyramids containing a single quantum dot (SQD) near the mesa top 12 . This unique class of SQD arrays in which the QD locations are controllable to within a few nm is synthesized using size-reducing epitaxial growth on nanomesas.…”

“…The edge orientations of nanomesas were chosen so that the accompanying surface-curvature stress-gradients direct preferentially the migration of adatoms symmetrically from the sidewalls to the mesa top during growth. This ensures spatially-selective growth on mesa tops 12,14,17 . The approach, dubbed substrate-encoded size-reducing epitaxy (SESRE) 12,14,17,18 enables accommodation of QD forming material combinations with significant lattice mismatch owing to the strain relaxation at the "free" surfaces of the laterally nanoscale mesas, unlike growth in arrays of pits that restrict the material combination to nearly lattice matched 19 .…”

“…This ensures spatially-selective growth on mesa tops 12,14,17 . The approach, dubbed substrate-encoded size-reducing epitaxy (SESRE) 12,14,17,18 enables accommodation of QD forming material combinations with significant lattice mismatch owing to the strain relaxation at the "free" surfaces of the laterally nanoscale mesas, unlike growth in arrays of pits that restrict the material combination to nearly lattice matched 19 . Following such approach, we previously reported arrays of GaAs/In0.5Ga0.5As/GaAs SQD on the mesa top (MTSQD) exhibiting single photo emission purity ~ 99% (g (2) (0) < 0.02) 13 .…”

“…However, controlling simultaneously the spatial and spectral uniformity adequately for either the dominantly explored semiconductor QD --the 3D island QD-or defect-based SPSs is still a great challenge 2,8,11 . In this paper we report: (a) the realization of a new class of semiconductor mesa top single quantum dots (MTSQDs) [12][13][14] in arrays (Fig. 1(a)) whose single photon emission purity is ~ 99.5% at 18K and as-grown spectral uniformity is < 2nm across a 5×8 array distributed over 1000μm 2 (Fig.…”

“…Together, this opens the pathway to the fabrication of on-chip integrated QOCs. To this end, we also report here a design for the integration of such buried MTSQDs with the basic light manipulating building units of circuits which can control QD emission rate, direct and guide photon emission utilizing the collective Mie mode of dielectric building blocks (DBBs) 12,15,16 as schematically shown as transparent blocks in Fig. 1(f).…”