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arXiv · 1101.2180

Polarization transitions in Quantum Dot Quantum Well Arrays

Ethan Brown·Kieran Mullen
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Abstract

With the improvement in fabrication techniques it is now possible to produce atom-like semiconductor structures with unique electronic properties. This makes possible periodic arrays of nano-structures in which the Coulomb interaction, polarizability, and tunneling may all be varied. We study the collective properties of 2D arrays and 3D face centered cubic lattices of singly-charged nano-spherical shells, sometimes called `quantum-dot quantum wells' or `core-shell quantum dots.' We find that for square arrays, the classical groundstate is an Ising anti-ferroelectret (AFE), while the quantum groundstate undergoes a transition from a uniform state to an AFE. The triangular lattice, in contrast, displays properties characteristic of frustration. Three dimensional face-centered cubic lattices polarize in planes, with each layer alternating in direction. We discuss the possible experimental signals of these transitions.

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Ethan Brown, Kieran Mullen. 2011-01-11. Polarization transitions in Quantum Dot Quantum Well Arrays. https://doi.org/10.1088/0953-8984%2F23%2F45%2F455301

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