# Optimizing electronic structure simulations on a trapped-ion quantum computer using problem decomposition

@article{Kawashima2021OptimizingES, title={Optimizing electronic structure simulations on a trapped-ion quantum computer using problem decomposition}, author={Yukio Kawashima and Erika Lloyd and Marc P. Coons and Yun Seong Nam and Shunji Matsuura and Alejandro J Garza and Sonika Johri and Lee M J Huntington and Valentin Senicourt and Andrii O. Maksymov and Jason H. V. Nguyen and Jungsang Kim and Nima Alidoust and Arman Zaribafiyan and Takeshi Yamazaki}, journal={Communications Physics}, year={2021}, volume={4}, pages={1-9} }

Quantum computers have the potential to advance material design and drug discovery by performing costly electronic structure calculations. A critical aspect of this application requires optimizing the limited resources of the quantum hardware. Here, we experimentally demonstrate an end-to-end pipeline that focuses on minimizing quantum resources while maintaining accuracy. Using density matrix embedding theory as a problem decomposition technique, and an ion-trap quantum computer, we simulate a…

## 13 Citations

### Ab initio Quantum Simulation of Strongly Correlated Materials with Quantum Embedding

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This work integrates the divide-and-conquer approaches into the variational quantum eigensolver (VQE) for large-scale quantum computational chemistry simulations, and should encourage further studies of using the philosophy of DC to solve electronic structure problems on quantum computers.

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- PhysicsPRX Quantum
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We present calculations of both the ground and excited state energies of spin defects in solids carried out on a quantum computer, using a hybrid classical/quantum protocol. We focus on the…

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- PhysicsPhysical Review B
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### Periodic Plane-Wave Electronic Structure Calculations on Quantum Computers

- Physics, Chemistry
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A procedure for deﬁning virtual spaces, and the periodic one-electron and two-electron integrals, for plane-wave second quantized Hamiltonians has been developed and demonstrated using full…

### Leveraging small scale quantum computers with unitarily downfolded Hamiltonians

- Computer Science
- 2022

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- Physics
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Quantum imaginary time evolution (QITE) is one of the promising candidates for ﬁnding eigenvalues and eigenstates of a Hamiltonian. However, the original QITE proposal [Nat. Phys. 16, 205-210…

### Tangelo: An Open-source Python Package for End-to-end Chemistry Workflows on Quantum Computers

- Computer Science
- 2022

The design choices, philosophy, and main features of Tangelo are outlined, which can be used to explore quantum computing applications such as open-shell systems, excited states, or more industrially-relevant systems by leveraging problem decomposition at scale.

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