Quantum hardware demonstrations of relativistic calculations of molecular electric dipole moments: from light to heavy systems using Variational Quantum Eigensolver

• URL: http://arxiv.org/abs/2406.04992v1
• Date: Fri, 7 Jun 2024 15:04:28 GMT
• Title: Quantum hardware demonstrations of relativistic calculations of molecular electric dipole moments: from light to heavy systems using Variational Quantum Eigensolver
• Authors: Palak Chawla, Shweta, K. R. Swain, Tushti Patel, Renu Bala, Disha Shetty, Kenji Sugisaki, Sudhindu Bikash Mandal, Jordi Riu, Jan Nogue, V. S. Prasannaa, B. P. Das,
• Abstract summary: This study extends the Variational Quantum Eigensolver (VQE) algorithm to the relativistic regime. We carry out 18-qubit quantum simulations to obtain ground state energies as well as PDMs of single-valence diatomic molecules. We measure the PDM of the moderately heavy SrH and SrF molecules on the optimized unitary coupled cluster state.
• Score: 0.4074484551332309
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The quantum-classical hybrid Variational Quantum Eigensolver (VQE) algorithm is recognized to be the method of choice to obtain ground state energies of quantum many-body systems in the noisy intermediate scale quantum (NISQ) era. This study not only extends the VQE algorithm to the relativistic regime, but also calculates a property other than energy, namely the molecular permanent electric dipole moment (PDM). We carry out 18-qubit quantum simulations to obtain ground state energies as well as PDMs of single-valence diatomic molecules, ranging from the light BeH to the heavy radioactive RaH molecule. We investigate the correlation trends in these systems as well as access the precision in our results. Furthermore, we measure the PDM of the moderately heavy SrH and SrF molecules on the optimized unitary coupled cluster state, using the state-of-the-art IonQ Aria-I quantum computer in an active space of 6 qubits. The associated quantum circuits for these computations were extensively optimized in view of limitations imposed by NISQ hardware. To that end, we employ an array of techniques, including the use of point group symmetries, integrating ZX-Calculus into our pipeline-based circuit optimization, and energy sort VQE procedure. Through these methods, we compress our 6-qubit quantum circuit from 280 two-qubit gates to 37 two-qubit gates (with a marginal trade-off of 0.33 and 0.31 percent in the PDM for SrH and SrF in their respective 6-spin orbital active spaces). We anticipate that our proof-of-concept demonstration lays the groundwork for future quantum hardware calculations involving heavy atoms and molecules.

Related papers

• VQE calculations on a NISQ era trapped ion quantum computer using a multireference unitary coupled cluster ansatz: application to the BeH$_2$ insertion problem [0.0]
  We report the ground state energy of the BeH$ Forte$ molecule in a geometry where strong correlation effects are significant. In order to carry out our intended 12-qubit computation on a noisy intermediate scale quantum era trapped ion hardware, we perform a series of resource reduction techniques.
  arXiv  Detail & Related papers  (2025-04-09T16:52:37Z)
• Non-unitary Coupled Cluster Enabled by Mid-circuit Measurements on Quantum Computers [37.69303106863453]
  We propose a state preparation method based on coupled cluster (CC) theory, which is a pillar of quantum chemistry on classical computers. Our approach leads to a reduction of the classical computation overhead, and the number of CNOT and T gates by 28% and 57% on average.
  arXiv  Detail & Related papers  (2024-06-17T14:10:10Z)
• Compressed-sensing Lindbladian quantum tomography with trapped ions [44.99833362998488]
  Characterizing the dynamics of quantum systems is a central task for the development of quantum information processors. We propose two different improvements of Lindbladian quantum tomography (LQT) that alleviate previous shortcomings.
  arXiv  Detail & Related papers  (2024-03-12T09:58:37Z)
• Precision ground-state energy calculation for the water molecule on a superconducting quantum processor [0.0]
  The accurate computation of properties of large molecular systems is classically infeasible and is one of the applications in which it is hoped that quantum computers will demonstrate an advantage over classical devices. Here, we apply the Quantum Computed Moments (QCM) approach combined with a variety of noise-mitigation techniques to an 8 qubit/spin-orbital representation of the water molecule (H$O). A noise-stable improvement on the variational result for a 4-excitation trial-state (circuit depth 25, 22 CNOTs) was obtained, with the ground-state energy computed to be within $1.4pm1.2$ m
  arXiv  Detail & Related papers  (2023-11-05T01:05:58Z)
• A qubit-ADAPT Implementation for H$_2$ Molecules using an Explicitly Correlated Basis [28.279056210896716]
  In the era of non-fault tolerant quantum devices, ADAPT algorithms are considered to be a promising approach for assisting classical machines with finding solution on computationally hard problems. In this work, the ADAPT algorithm has been combined with a first-quantized formulation for the hydrogen molecule in Born-Oppenheimer approximation.
  arXiv  Detail & Related papers  (2023-08-14T16:44:29Z)
• Orbital-optimized pair-correlated electron simulations on trapped-ion quantum computers [0.471876092032107]
  Variational quantum eigensolvers (VQE) are among the most promising approaches for solving electronic structure problems on quantum computers. A critical challenge for VQE in practice is that one needs to strike a balance between the expressivity of the VQE ansatz versus the number of quantum gates required to implement the ansatz. We run end-to-end VQE algorithms with up to 12 qubits and 72 variational parameters - the largest full VQE simulation with a correlated wave function on quantum hardware.
  arXiv  Detail & Related papers  (2022-12-05T18:40:54Z)
• Iterative Qubit Coupled Cluster using only Clifford circuits [36.136619420474766]
  An ideal state preparation protocol can be characterized by being easily generated classically. We propose a method that meets these requirements by introducing a variant of the iterative qubit coupled cluster (iQCC) We demonstrate the algorithm's correctness in ground-state simulations and extend our study to complex systems like the titanium-based compound Ti(C5H5)(CH3)3 with a (20, 20) active space.
  arXiv  Detail & Related papers  (2022-11-18T20:31:10Z)
• Molecular electric dipole moments: from light to heavy molecules using a relativistic VQE algorithm [0.0]
  We extend the VQE algorithm to the relativistic regime and carry out quantum simulations to obtain ground state energies. We study the correlation trends in these systems as well as assess the precision in our results within our active space of 12 qubits.
  arXiv  Detail & Related papers  (2022-11-13T13:57:52Z)
• The Cost of Improving the Precision of the Variational Quantum Eigensolver for Quantum Chemistry [0.0]
  We study how various types of errors affect the variational quantum eigensolver (VQE) We find that the optimal way of running the hybrid classical-quantum optimization is to allow some noise in intermediate energy evaluations.
  arXiv  Detail & Related papers  (2021-11-09T06:24:52Z)
• Computing molecular excited states on a D-Wave quantum annealer [52.5289706853773]
  We demonstrate the use of a D-Wave quantum annealer for the calculation of excited electronic states of molecular systems. These simulations play an important role in a number of areas, such as photovoltaics, semiconductor technology and nanoscience.
  arXiv  Detail & Related papers  (2021-07-01T01:02:17Z)
• Quantum-Classical Hybrid Algorithm for the Simulation of All-Electron Correlation [58.720142291102135]
  We present a novel hybrid-classical algorithm that computes a molecule's all-electron energy and properties on the classical computer. We demonstrate the ability of the quantum-classical hybrid algorithms to achieve chemically relevant results and accuracy on currently available quantum computers.
  arXiv  Detail & Related papers  (2021-06-22T18:00:00Z)
• Benchmarking adaptive variational quantum eigensolvers [63.277656713454284]
  We benchmark the accuracy of VQE and ADAPT-VQE to calculate the electronic ground states and potential energy curves. We find both methods provide good estimates of the energy and ground state. gradient-based optimization is more economical and delivers superior performance than analogous simulations carried out with gradient-frees.
  arXiv  Detail & Related papers  (2020-11-02T19:52:04Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.