Room Temperature Spin Filtering and Quantum Transport with Transition Metal-Doped Silicon Quantum Dot

Hemant Arora; Arup Samanta

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arXiv · 2402.17461

Room Temperature Spin Filtering and Quantum Transport with Transition Metal-Doped Silicon Quantum Dot

Hemant Arora·Arup Samanta

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Abstract

Spin filtering is a fundamental operation in spintronics, enabling the generation and detection of spin-polarized carriers. Here, we proposed and theoretically demonstrated that a 3d transition metal (TM) doped silicon quantum dot (SiQD) is a suitable candidate for spin filter device at room temperature. Using density functional theory (DFT), we investigate the structure, electronic properties, and magnetic behavior of TM-SiQD. Our calculations demonstrate that Mn-doped SiQD exhibits the highest stability. The designed spin-filter device using Mn-doped SiQD shows a spin-filtering efficiency of 99.9% at 300K electrode temperature along with very high conductance. This remarkable efficiency positions it as a promising candidate for room-temperature spintronic devices.

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Hemant Arora, Arup Samanta. 2024-02-27. Room Temperature Spin Filtering and Quantum Transport with Transition Metal-Doped Silicon Quantum Dot. https://arxiv.org/abs/2402.17461

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