Approximating quantum thermodynamic properties using DFT
- URL: http://arxiv.org/abs/2201.05563v2
- Date: Mon, 25 Apr 2022 12:54:09 GMT
- Title: Approximating quantum thermodynamic properties using DFT
- Authors: Krissia Zawadzki, Amy Skelt and Irene D'Amico
- Abstract summary: We compare simple' and hybrid' approximations to the average work and entropy variation built on static density functional theory concepts.
Our results confirm that a hybrid' approach requires a very good approximation of the initial and, for the entropy, final states of the system.
This approach should be particularly efficient when many-body effects are not increased by the driving Hamiltonian.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The fabrication, utilisation, and efficiency of quantum technologies rely on
a good understanding of quantum thermodynamic properties. Many-body systems are
often used as hardware for these quantum devices, but interactions between
particles make the complexity of related calculations grow exponentially with
the system size. Here we explore and systematically compare `simple' and
`hybrid' approximations to the average work and entropy variation built on
static density functional theory concepts. These approximations are
computationally cheap and could be applied to large systems. We exemplify them
considering driven one-dimensional Hubbard chains and show that, for `simple'
approximations and low to medium temperatures, it pays to consider a good
Kohn-Sham Hamiltonian to approximate the driving Hamiltonian. Our results
confirm that a `hybrid' approach, requiring a very good approximation of the
initial and, for the entropy, final states of the system, provides great
improvements. This approach should be particularly efficient when many-body
effects are not increased by the driving Hamiltonian.
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