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arXiv · 1810.06517

Coherent long-range transfer of two-electron states in ac-driven triple quantum dots

Abstract

Preparation and transfer of quantum states is a fundamental task in quantum information. We propose a protocol to prepare a state in the left and center quantum dots of a triple dot array and transfer it directly to the center and right dots. Initially the state in the left and center dots is prepared combining the exchange interaction and magnetic field gradients. Once in the desired state, ac gate voltages in the outer dots are switched on, allowing to select a given photoassisted long-range path and to transfer the prepared state directly from one edge to the other with high fidelity. We investigate the effect of charge noise on the protocol and propose a configuration in which the transfer can be performed with high fidelity. Our proposal can be experimentally implemented and is a promising avenue for transferring quantum states between two spatially separated two-level systems.

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Jordi Picó-Cortés, Fernando Gallego-Marcos, Gloria Platero. 2018-10-16. Coherent long-range transfer of two-electron states in ac-driven triple quantum dots. https://doi.org/10.1103/physrevb.99.155421

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