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arXiv · 2012.09231

Quantum Algorithm for Simulating Single-Molecule Electron Transport

Soran Jahangiri·Juan Miguel Arrazola·Alain Delgado
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Abstract

An accurate description of electron transport at a molecular level requires a precise treatment of quantum effects. These effects play a crucial role in determining the electron transport properties of single molecules, such as current-voltage curves, which can be challenging to simulate classically. Here we introduce a quantum algorithm to efficiently calculate the electronic current through single-molecule junctions in the weak-coupling regime. We show that a quantum computer programmed to simulate vibronic transitions between different charge states of a molecule can be used to compute sequential electron transfer rates and electric current. In the harmonic approximation, the algorithm can be implemented using Gaussian boson sampling devices, which are a near-term platform for photonic quantum computing. We apply the algorithm to simulate the current and conductance of a magnesium porphine molecule. The simulations demonstrate quantum effects that are manifested as discrete steps in the current and conductance, in agreement with experimental and theoretical data.

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Soran Jahangiri, Juan Miguel Arrazola, Alain Delgado. 2020-12-16. Quantum Algorithm for Simulating Single-Molecule Electron Transport. https://arxiv.org/abs/2012.09231

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