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arXiv · 2505.11377

TensorMixedStates: a Julia library for simulating pure and mixed quantum states using matrix product states

Jérôme Houdayer·Grégoire Misguich
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Abstract

We introduce TensorMixedStates, a Julia library built on top of ITensor which allows the simulation of quantum systems in the presence of dissipation using matrix product states (MPS). It offers three key features: i) it implements the MPS representation for mixed states along with associated operations, in particular the time evolution according to a Lindblad equation or discrete time evolution using non-unitary gates (quantum channels), ii) it is based on ITensor, which has proven its effectiveness and which gives access to efficient low-level tensor manipulation as well as state-of-the-art algorithms (like DMRG or TDVP), finally iii) it presents a user-friendly interface allowing users to write sophisticated simulations for pure and mixed quantum states in a few lines of code.

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Jérôme Houdayer, Grégoire Misguich. 2025-05-16. TensorMixedStates: a Julia library for simulating pure and mixed quantum states using matrix product states. https://doi.org/10.21468/scipostphyscodeb.72

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