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arXiv · 2505.21221

Quantum algorithms for solving a drift-diffusion equation: A complexity analysis

Ellen Devereux·Animesh Datta
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Abstract

We present four quantum algorithms for solving a multidimensional drift-diffusion equation. They rely on a quantum linear system solver, a quantum Hamiltonian simulation, a quantum random walk, and the quantum Fourier transform. We compare the complexities of these methods to their classical counterparts, finding that diagonalization via the quantum Fourier transform offers a quantum computational advantage for solving linear partial differential equations at a fixed final time. We employ a multidimensional amplitude estimation process to extract the full probability distribution from the quantum computer.

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Ellen Devereux, Animesh Datta. 2025-05-27. Quantum algorithms for solving a drift-diffusion equation: A complexity analysis. https://doi.org/10.1103/1fw9-h14w

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