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arXiv · 2204.03890

Inelastic Cotunneling Resonances in the Coulomb-Blockade Transport in Donor-Atom Transistors

Pooja Yadav·Soumya Chakraborty·Daniel Moraru·Arup Samanta
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Abstract

We report finite-bias characteristics of electrical transport through phosphorus donors in silicon nanoscale transistors, in which we observe inelastic-cotunneling current in the Coulomb blockade region. The cotunneling current appears like a resonant-tunneling current peak emerging from the excited state at the crossover between blockade and non-blockade regions. These cotunneling features are unique, since the inelastic-cotunneling currents have so far been reported either as a broader hump or as a continuous increment of current. This finding is ascribed purely due to excitation-related inelastic cotunneling involving the ground and excited states. Theoretical calculations were performed for a two-level quantum dot, supporting our experimental observation.

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Pooja Yadav, Soumya Chakraborty, Daniel Moraru, Arup Samanta. 2022-04-08. Inelastic Cotunneling Resonances in the Coulomb-Blockade Transport in Donor-Atom Transistors. https://doi.org/10.1116/5.0097509

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