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arXiv:2403.06522

Quantum Entanglement in a Diluted Magnetic Semiconductor Quantum Dot

Manish Kumar Mehta, J. T. Andrews, Pratima Sen

Published Mar 11, 2024• 0 citations
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Abstract

We investigated the entanglement in a diluted magnetic semiconductor quantum dot, crucial for quantum technologies. Despite their potential, these systems exhibit low extraction rates. We explore self-assembled InGaAs quantum dots, focusing on entanglement between them based on spin states. Our analysis involves defining wavefunctions, employing density matrix operators, and measuring entanglement entropy. Numerical assessments reveal few promising pairs among various quantum dot combinations that exhibit significant entanglement. Additionally, this work discusses theoretical developments and statistical evaluations of entanglement in diluted magnetic semiconductor quantum dots, providing insights into their potential for quantum applications.

DOI
10.48550/arxiv.2403.06522

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We investigated the entanglement in a diluted magnetic semiconductor quantum dot, crucial for quantum technologies. Despite their potential, these systems exhibit low extraction rates. We explore self-assembled InGaAs quantum dots, focusing on entanglement between them based on spin states. Our analysis involves defining wavefunctions, employing density matrix operators, and measuring entanglement entropy. Numerical assessments reveal few promising pairs among various quantum dot combinations that exhibit significant entanglement. Additionally, this work discusses theoretical developments and statistical evaluations of entanglement in diluted magnetic semiconductor quantum dots, providing insights into their potential for quantum applications.
We define the qubit as a pair of singlet and triplet states of two electrons in a He-type quantum dot (QD) placed in a diluted magnetic semiconductor (DMS) medium. The molecular field is here essential as it removes the degeneracy of the triplet state and strongly enhances the Zeeman splitting. Methods of qubit rotation as well as two-qubit operations are suggested. The system of a QD in a DMS is described in a way which allows an analysis of the decoherence due to spin waves in the DMS subsystem.
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