A cavity design that combines a "bottom-up" synthesized semiconductor nanowire with a "top-down" fabricated one-dimensional
photonic crystal (PhC) has been proposed. In this paper, we present a detailed study of the characteristics of
the nanowire-based Bragg mirror and the resulting nanocavities, using finite-difference time-domain (FDTD) code.
Based on this proposal, we demonstrate ultra-high Quality factor (<i>Q</i>) on the order of one million, an increase of three
orders of magnitude over the Quality factor of an as-grown nanowire. We believe that our design will offer a feasible
platform to develop various nanowire-based photonic devices, for example, quantum optical devices that operate in the