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arXiv · 1409.2534

Theory and design of quantum light sources from quantum dots embedded in semiconductor-nanowire photonic crystal systems

Gerasimos Angelatos·Stephen Hughes
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Abstract

We introduce a new platform for realizing on-chip quantum electrodynamics using photonic crystal waveguide structures comprised of periodic nanowire arrays with embedded semiconductor quantum dots to act as quantum light sources. These nanowire-based structures, which can now be fabricated with excellent precision, are found to produce waveguide Purcell factors exceeding 100 and on-chip beta factors up to 99%. We investigate the fundamental optical properties of photonic crystal waveguides and finite-size structures using both photonic band structure calculations and rigorous Green function computations which allows us to obtain the modal properties and the local density of photon states. A comparison with slab-based photonic crystals is also made and we a highlight key advantages in the nanowire system, including the potential to minimize extrinsic scattering losses and produce high theoretical Purcell factors and beta-factors on-chip. We also demonstrate that these structures exhibit rich photonic Lamb shifts over broadband frequencies.

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Gerasimos Angelatos, Stephen Hughes. 2014-09-08. Theory and design of quantum light sources from quantum dots embedded in semiconductor-nanowire photonic crystal systems. https://doi.org/10.1103/physrevb.90.205406

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