The advent of fully variational quantum eigensolvers using a hybrid multiresolution approach

• URL: http://arxiv.org/abs/2410.19116v1
• Date: Thu, 24 Oct 2024 19:37:16 GMT
• Title: The advent of fully variational quantum eigensolvers using a hybrid multiresolution approach
• Authors: Fabian Langkabel, Stefan Knecht, Jakob S. Kottmann,
• Abstract summary: We show a fully variational approach to the electronic structure problem by variationally optimizing the orbitals representing the second quantized Hamiltonian. We then showcase explicit numerical protocols and highlight the quantum circuit's effects on determining the optimal orbital basis.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: In electronic structure theory, variational computing offers a valuable paradigm for the approximation of electronic ground states. However, for historical reasons, this principle is mostly restricted to model-chemistries in pre-defined fixed basis sets. Especially in quantum computation, these model-chemistries are far from an accurate description of the initial electronic Hamiltonian. Throwing down the gauntlet, we here demonstrate a fully variational approach to the electronic structure problem by variationally optimizing the orbitals representing the second quantized Hamiltonian alongside a quantum circuit that generates the many-electron wavefunction. To this end, the orbitals are represented within an adaptive multi-wavelet format, guaranteeing numerical precision. We then showcase explicit numerical protocols and highlight the quantum circuit's effects on determining the optimal orbital basis.

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