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arXiv · 1207.1099

Y-junction splitting spin states of moving quantum dot

Tuukka Hiltunen·Ari Harju
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Abstract

The development of a working quantum computer utilizing electron spin states as qubits is a major goal for many theorists and experimentalists. The future applications of quantum information technology would also require a reliable method for the transportation of quantum information. A promising such method is the propagation of electrons by a surface acoustic wave (SAW). In this paper, we simulate the SAW transfer of two interacting electrons through a Y-shaped junction. Our results show that the singlet and triplet states can be differentiated in the Y-junction by an electrostatic detuning potential, an effect that could be used in for example measuring the state of a two-spin qubit.

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Tuukka Hiltunen, Ari Harju. 2012-07-04. Y-junction splitting spin states of moving quantum dot. https://doi.org/10.1103/physrevb.86.121301

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