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Davidsson J, Onizhuk M, Vorwerk C, Galli G. Discovery of atomic clock-like spin defects in simple oxides from first principles. Nat Commun 2024; 15:4812. [PMID: 38844443 PMCID: PMC11156963 DOI: 10.1038/s41467-024-49057-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 05/17/2024] [Indexed: 06/09/2024] Open
Abstract
Virtually noiseless due to the scarcity of spinful nuclei in the lattice, simple oxides hold promise as hosts of solid-state spin qubits. However, no suitable spin defect has yet been found in these systems. Using high-throughput first-principles calculations, we predict spin defects in calcium oxide with electronic properties remarkably similar to those of the NV center in diamond. These defects are charged complexes where a dopant atom - Sb, Bi, or I - occupies the volume vacated by adjacent cation and anion vacancies. The predicted zero phonon line shows that the Bi complex emits in the telecommunication range, and the computed many-body energy levels suggest a viable optical cycle required for qubit initialization. Notably, the high-spin nucleus of each dopant strongly couples to the electron spin, leading to many controllable quantum levels and the emergence of atomic clock-like transitions that are well protected from environmental noise. Specifically, the Hanh-echo coherence time increases beyond seconds at the clock-like transition in the defect with 209Bi. Our results pave the way to designing quantum states with long coherence times in simple oxides, making them attractive platforms for quantum technologies.
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Affiliation(s)
- Joel Davidsson
- Department of Physics, Chemistry and Biology, Linköping University, SE-581 83, Linköping, Sweden.
| | - Mykyta Onizhuk
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA.
| | - Christian Vorwerk
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA
| | - Giulia Galli
- Pritzker School of Molecular Engineering and Department of Chemistry, University of Chicago, Chicago, IL, 60637, USA.
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, IL, 60439, USA.
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2
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Mackrodt WC, Platonenko A, Pascale F, Dovesi R. The energies and charge and spin distributions in the low-lying levels of singlet and triplet N2V defects in diamond from direct variational calculations of the excited states. J Chem Phys 2024; 160:034705. [PMID: 38230814 DOI: 10.1063/5.0178893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 12/25/2023] [Indexed: 01/18/2024] Open
Abstract
This paper reports the energies and charge and spin distributions of the low-lying excited states in singlet and triplet N2V defects in diamond from direct Δ-SCF calculations based on Gaussian orbitals within the B3LYP, PBE0, and HSE06 functionals. They assign the observed absorption at 2.463 eV, first reported by Davies et al. [Proc. R. Soc. London 351, 245 (1976)], to the excitation of a N(sp3) lone-pair electron in the singlet and triplet states, respectively, with estimates of ∼1.1 eV for that of the unpaired electrons, C(sp3). In both cases, the excited states are predicted to be highly local and strongly excitonic with 81% of the C(sp3) and 87% of the N(sp3) excited charges localized at the three C atoms nearest neighbor (nn) to the excitation sites. Also reported are the higher excited gap states of both the N lone pair and C unpaired electron. Calculated excitation energies of the bonding sp3 hybrids of the C atoms nn to the four inner atoms are close to that of the bulk, which indicates that the N2V defect is largely a local defect. The present results are in broad agreement with those reported by Udvarhelyi et al. [Phys. Rev. B 96, 155211 (2017)] from plane wave HSE06 calculations, notably for the N lone pair excitation energy, for which both predict an energy of ∼2.7 eV but with a difference of ∼0.5 eV for the excitation of the unpaired electron.
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Affiliation(s)
- William C Mackrodt
- Department of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, England, United Kingdom
| | - Alexander Platonenko
- Institute of Solid State Physics, University of Latvia, 8 Kengaraga Street, LV1063 Riga, Latvia
| | - Fabien Pascale
- Université de Lorraine - Nancy, CNRS, Laboratoire de Physique et Chimie Théoriques, UMR 7019, Vandoeuvre-les-Nancy, France
| | - Roberto Dovesi
- Accademia delle Scienze di Torino, Via Accademia delle Scienze, 6, 10123 Torino, Italy
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3
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Jin Y, Yu VWZ, Govoni M, Xu AC, Galli G. Excited State Properties of Point Defects in Semiconductors and Insulators Investigated with Time-Dependent Density Functional Theory. J Chem Theory Comput 2023. [PMID: 38039161 DOI: 10.1021/acs.jctc.3c00986] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2023]
Abstract
We present a formulation of spin-conserving and spin-flip hybrid time-dependent density functional theory (TDDFT), including the calculation of analytical forces, which allows for efficient calculations of excited state properties of solid-state systems with hundreds to thousands of atoms. We discuss an implementation on both GPU- and CPU-based architectures along with several acceleration techniques. We then apply our formulation to the study of several point defects in semiconductors and insulators, specifically the negatively charged nitrogen-vacancy and neutral silicon-vacancy centers in diamond, the neutral divacancy center in 4H silicon carbide, and the neutral oxygen-vacancy center in magnesium oxide. Our results highlight the importance of taking into account structural relaxations in excited states in order to interpret and predict optical absorption and emission mechanisms in spin defects.
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Affiliation(s)
- Yu Jin
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Victor Wen-Zhe Yu
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Marco Govoni
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Department of Physics, Computer Science, and Mathematics, University of Modena and Reggio Emilia, Modena 41125, Italy
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Andrew C Xu
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Giulia Galli
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
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4
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Verma S, Mitra A, Jin Y, Haldar S, Vorwerk C, Hermes MR, Galli G, Gagliardi L. Optical Properties of Neutral F Centers in Bulk MgO with Density Matrix Embedding. J Phys Chem Lett 2023; 14:7703-7710. [PMID: 37606586 DOI: 10.1021/acs.jpclett.3c01875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
The optical spectra of neutral oxygen vacancies (F0 centers) in the bulk MgO lattice are investigated using density matrix embedding theory. The impurity Hamiltonian is solved with the complete active space self-consistent field and second-order n-electron valence state perturbation theory (NEVPT2-DMET) multireference methods. To estimate defect-localized vertical excitation energies at the nonembedding and thermodynamic limits, a double extrapolation scheme is employed. The extrapolated NEVPT2-DMET vertical excitation energy value of 5.24 eV agrees well with the experimental absorption maxima at 5.03 eV, whereas the excitation energy value of 2.89 eV at the relaxed triplet defect-localized state geometry overestimates the experimental emission at 2.4 eV by only nearly 0.5 eV, indicating the involvement of the triplet-singlet decay pathway.
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Affiliation(s)
- Shreya Verma
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Abhishek Mitra
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Yu Jin
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Soumi Haldar
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Christian Vorwerk
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Matthew R Hermes
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Giulia Galli
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Laura Gagliardi
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
- Argonne National Laboratory, 9700 S. Cass Avenue, Lemont, Illinois 60439, United States
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5
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Spin-defect qubits in two-dimensional transition metal dichalcogenides operating at telecom wavelengths. Nat Commun 2022; 13:7501. [PMID: 36473851 PMCID: PMC9723673 DOI: 10.1038/s41467-022-35048-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 11/16/2022] [Indexed: 12/12/2022] Open
Abstract
Solid state quantum defects are promising candidates for scalable quantum information systems which can be seamlessly integrated with the conventional semiconductor electronic devices within the 3D monolithically integrated hybrid classical-quantum devices. Diamond nitrogen-vacancy (NV) center defects are the representative examples, but the controlled positioning of an NV center within bulk diamond is an outstanding challenge. Furthermore, quantum defect properties may not be easily tuned for bulk crystalline quantum defects. In comparison, 2D semiconductors, such as transition metal dichalcogenides (TMDs), are promising solid platform to host a quantum defect with tunable properties and a possibility of position control. Here, we computationally discover a promising defect family for spin qubit realization in 2D TMDs. The defects consist of transition metal atoms substituted at chalcogen sites with desirable spin-triplet ground state, zero-field splitting in the tens of GHz, and strong zero-phonon coupling to optical transitions in the highly desirable telecom band.
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6
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Yu VWZ, Govoni M. GPU Acceleration of Large-Scale Full-Frequency GW Calculations. J Chem Theory Comput 2022; 18:4690-4707. [PMID: 35913080 DOI: 10.1021/acs.jctc.2c00241] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Many-body perturbation theory is a powerful method to simulate electronic excitations in molecules and materials starting from the output of density functional theory calculations. By implementing the theory efficiently so as to run at scale on the latest leadership high-performance computing systems it is possible to extend the scope of GW calculations. We present a GPU acceleration study of the full-frequency GW method as implemented in the WEST code. Excellent performance is achieved through the use of (i) optimized GPU libraries, e.g., cuFFT and cuBLAS, (ii) a hierarchical parallelization strategy that minimizes CPU-CPU, CPU-GPU, and GPU-GPU data transfer operations, (iii) nonblocking MPI communications that overlap with GPU computations, and (iv) mixed precision in selected portions of the code. A series of performance benchmarks has been carried out on leadership high-performance computing systems, showing a substantial speedup of the GPU-accelerated version of WEST with respect to its CPU version. Good strong and weak scaling is demonstrated using up to 25 920 GPUs. Finally, we showcase the capability of the GPU version of WEST for large-scale, full-frequency GW calculations of realistic systems, e.g., a nanostructure, an interface, and a defect, comprising up to 10 368 valence electrons.
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Affiliation(s)
- Victor Wen-Zhe Yu
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Marco Govoni
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.,Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
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7
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Vorwerk C, Sheng N, Govoni M, Huang B, Galli G. Quantum embedding theories to simulate condensed systems on quantum computers. NATURE COMPUTATIONAL SCIENCE 2022; 2:424-432. [PMID: 38177872 DOI: 10.1038/s43588-022-00279-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 06/14/2022] [Indexed: 01/06/2024]
Abstract
Quantum computers hold promise to improve the efficiency of quantum simulations of materials and to enable the investigation of systems and properties that are more complex than tractable at present on classical architectures. Here, we discuss computational frameworks to carry out electronic structure calculations of solids on noisy intermediate-scale quantum computers using embedding theories, and we give examples for a specific class of materials, that is, solid materials hosting spin defects. These are promising systems to build future quantum technologies, such as quantum computers, quantum sensors and quantum communication devices. Although quantum simulations on quantum architectures are in their infancy, promising results for realistic systems appear to be within reach.
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Affiliation(s)
- Christian Vorwerk
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
| | - Nan Sheng
- Department of Chemistry, University of Chicago, Chicago, IL, USA
| | - Marco Govoni
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, IL, USA.
| | - Benchen Huang
- Department of Chemistry, University of Chicago, Chicago, IL, USA
| | - Giulia Galli
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA.
- Department of Chemistry, University of Chicago, Chicago, IL, USA.
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, IL, USA.
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8
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Sheng N, Vorwerk C, Govoni M, Galli G. Green's Function Formulation of Quantum Defect Embedding Theory. J Chem Theory Comput 2022; 18:3512-3522. [PMID: 35648660 DOI: 10.1021/acs.jctc.2c00240] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We present a Green's function formulation of the quantum defect embedding theory (QDET) where a double counting scheme is rigorously derived within the G0W0 approximation. We then show the robustness of our methodology by applying the theory with the newly derived scheme to several defects in diamond. Additionally, we discuss a strategy to obtain converged results as a function of the size and composition of the active space. Our results show that QDET is a promising approach to investigate strongly correlated states of defects in solids.
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Affiliation(s)
- Nan Sheng
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Christian Vorwerk
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Marco Govoni
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States.,Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Giulia Galli
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.,Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States.,Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, United States
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9
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Mitra A, Pham HQ, Pandharkar R, Hermes MR, Gagliardi L. Excited States of Crystalline Point Defects with Multireference Density Matrix Embedding Theory. J Phys Chem Lett 2021; 12:11688-11694. [PMID: 34843250 DOI: 10.1021/acs.jpclett.1c03229] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Accurate and affordable methods to characterize the electronic structure of solids are important for targeted materials design. Embedding-based methods provide an appealing balance in the trade-off between cost and accuracy─particularly when studying localized phenomena. Here, we use the density matrix embedding theory (DMET) algorithm to study the electronic excitations in solid-state defects with a restricted open-shell Hartree-Fock (ROHF) bath and multireference impurity solvers, specifically, complete active space self-consistent field (CASSCF) and n-electron valence state second-order perturbation theory (NEVPT2). We apply the method to investigate the electronic excitations in an oxygen vacancy (OV) on a MgO(100) surface and find absolute deviations within 0.05 eV between DMET using the CASSCF/NEVPT2 solver, denoted as CAS-DMET/NEVPT2-DMET, and the nonembedded CASSCF/NEVPT2 approach. Next, we establish the practicality of DMET by extending it to larger supercells for the OV defect and a neutral silicon vacancy in diamond where the use of nonembedded CASSCF/NEVPT2 is extremely expensive.
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Affiliation(s)
- Abhishek Mitra
- Department of Chemistry, Chicago Center for Theoretical Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Hung Q Pham
- Department of Chemistry, University of Minnesota Twin Cities, Smith Hall, 207 Pleasant St SE, Minneapolis, Minnesota 55455-0431, United States
| | - Riddhish Pandharkar
- Department of Chemistry, Chicago Center for Theoretical Chemistry, University of Chicago, Chicago, Illinois 60637, United States
- Argonne National Laboratory, 9700 S. Cass Avenue, Lemont, Illinois 60439, United States
| | - Matthew R Hermes
- Department of Chemistry, Chicago Center for Theoretical Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Laura Gagliardi
- Argonne National Laboratory, 9700 S. Cass Avenue, Lemont, Illinois 60439, United States
- Department of Chemistry, Pritzker School of Molecular Engineering, James Franck Institute, Chicago Center for Theoretical Chemistry, University of Chicago, Chicago, Illinois 60637, United States
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10
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Ping Y, Smart TJ. Computational design of quantum defects in two-dimensional materials. NATURE COMPUTATIONAL SCIENCE 2021; 1:646-654. [PMID: 38217204 DOI: 10.1038/s43588-021-00140-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 09/15/2021] [Indexed: 01/15/2024]
Abstract
Missing atoms or atom substitutions (point defects) in crystal lattices in two-dimensional (2D) materials are potential hosts for emerging quantum technologies, such as single-photon emitters and spin quantum bits (qubits). First-principles-guided design of quantum defects in 2D materials is paving the way for rational spin qubit discovery. Here we discuss the frontier of first-principles theory development and the challenges in predicting the critical physical properties of point defects in 2D materials for quantum information technology, in particular for optoelectronic and spin-optotronic properties. Strong many-body interactions at reduced dimensionality require advanced electronic structure methods beyond mean-field theory. The great challenges for developing theoretical methods that are appropriate for strongly correlated defect states, as well as general approaches for predicting spin relaxation and the decoherence time of spin defects, are yet to be addressed.
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Affiliation(s)
- Yuan Ping
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA, USA.
| | - Tyler J Smart
- Department of Physics, University of California, Santa Cruz, CA, USA
- Lawrence Livermore National Laboratory, Livermore, CA, USA
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11
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Fujiwara M, Shikano Y. Diamond quantum thermometry: from foundations to applications. NANOTECHNOLOGY 2021; 32:482002. [PMID: 34416739 DOI: 10.1088/1361-6528/ac1fb1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Diamond quantum thermometry exploits the optical and electrical spin properties of colour defect centres in diamonds and, acts as a quantum sensing method exhibiting ultrahigh precision and robustness. Compared to the existing luminescent nanothermometry techniques, a diamond quantum thermometer can be operated over a wide temperature range and a sensor spatial scale ranging from nanometres to micrometres. Further, diamond quantum thermometry is employed in several applications, including electronics and biology, to explore these fields with nanoscale temperature measurements. This review covers the operational principles of diamond quantum thermometry for spin-based and all-optical methods, material development of diamonds with a focus on thermometry, and examples of applications in electrical and biological systems with demand-based technological requirements.
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Affiliation(s)
- Masazumi Fujiwara
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Yutaka Shikano
- Graduate School of Science and Technology, Gunma University, 4-2 Aramaki, Maebashi, Gunma 371-8510, Japan
- Quantum Computing Center, Keio University, 3-14-1 Hiyoshi, Kohoku, Yokohama 223-8522, Japan
- Institute for Quantum Studies, Chapman University, 1 University Dr, Orange, CA 92866, United States of America
- JST PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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12
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Ma H, Sheng N, Govoni M, Galli G. Quantum Embedding Theory for Strongly Correlated States in Materials. J Chem Theory Comput 2021; 17:2116-2125. [DOI: 10.1021/acs.jctc.0c01258] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- He Ma
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Nan Sheng
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Marco Govoni
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Giulia Galli
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, United States
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13
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Dong SS, Govoni M, Galli G. Machine learning dielectric screening for the simulation of excited state properties of molecules and materials. Chem Sci 2021; 12:4970-4980. [PMID: 34163744 PMCID: PMC8179553 DOI: 10.1039/d1sc00503k] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 02/12/2021] [Indexed: 11/21/2022] Open
Abstract
Accurate and efficient calculations of absorption spectra of molecules and materials are essential for the understanding and rational design of broad classes of systems. Solving the Bethe-Salpeter equation (BSE) for electron-hole pairs usually yields accurate predictions of absorption spectra, but it is computationally expensive, especially if thermal averages of spectra computed for multiple configurations are required. We present a method based on machine learning to evaluate a key quantity entering the definition of absorption spectra: the dielectric screening. We show that our approach yields a model for the screening that is transferable between multiple configurations sampled during first principles molecular dynamics simulations; hence it leads to a substantial improvement in the efficiency of calculations of finite temperature spectra. We obtained computational gains of one to two orders of magnitude for systems with 50 to 500 atoms, including liquids, solids, nanostructures, and solid/liquid interfaces. Importantly, the models of dielectric screening derived here may be used not only in the solution of the BSE but also in developing functionals for time-dependent density functional theory (TDDFT) calculations of homogeneous and heterogeneous systems. Overall, our work provides a strategy to combine machine learning with electronic structure calculations to accelerate first principles simulations of excited-state properties.
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Affiliation(s)
- Sijia S Dong
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory Lemont IL 60439 USA
- Pritzker School of Molecular Engineering, The University of Chicago Chicago IL 60637 USA
| | - Marco Govoni
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory Lemont IL 60439 USA
- Pritzker School of Molecular Engineering, The University of Chicago Chicago IL 60637 USA
| | - Giulia Galli
- Materials Science Division and Center for Molecular Engineering, Argonne National Laboratory Lemont IL 60439 USA
- Pritzker School of Molecular Engineering, The University of Chicago Chicago IL 60637 USA
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