2024 New's Items

Explicit block encodings of boundary value problems for many-body elliptic operators

Kharazi, T.
Alkadri, A. M.
Liu, J.-P.
Mandadapu, K. K.
Whaley, K. B.
2024

Simulation of physical systems is one of the most promising use cases of future digital quantum computers. In this work we systematically analyze the quantum circuit complexities of block encoding the discretized elliptic operators that arise extensively in numerical simulations for partial differential equations, including high-dimensional instances for many-body simulations. When restricted to rectangular domains with separable boundary conditions, we provide explicit circuits to block encode the many-body Laplacian with separable periodic, Dirichlet, Neumann, and Robin boundary...

Mechanochemically accelerated deconstruction of chemically recyclable plastics

Hua, M.
Peng, Z.
Guha, R. D.
Ruan, X.
Ng, K. C.
Demarteau, J.
Haber, S.
Fricke, S. N.
Reimer, J. A.
Salmeron, M. B.
Persson, K. A.
Wang, C.
Helms, B. A.
2024
Plastics redesign for circularity has primarily focused on monomer chemistries enabling faster deconstruction rates concomitant with high monomer yields. Yet, during deconstruction, polymer chains interact with their reaction medium, which remains underexplored in polymer reactivity. Here, we show that, when plastics are deconstructed in reaction media that promote swelling, initial rates are accelerated by over sixfold beyond those in small-molecule analogs. This unexpected acceleration is primarily tied to mechanochemical activation of strained polymer chains; however, changes in the...

The Interplay Between Electron Localization, Magnetic Order, and Jahn-Teller Distortion that Dictates LiMnO2 Phase Stability

Ronald L. Kam
Luca Binci
Aaron D. Kaplan
Kristin A. Persson
Nicola Marzari
Gerbrand Ceder
2024

The development of manganese (Mn)-rich cathodes for Li-ion batteries promises to alleviate potential supply chain bottlenecks in battery manufacturing. Fundamental challenges in Mn-rich cathodes arise from phenomena such as structural changes due to cooperative Jahn-Teller (JT) distortions of Mn3+ in octahedral environments, Mn migration, and phase transformations to spinel-like order, all of which affect the electrochemical performance. These physically complex phenomena motivate an ab initio re-examination of the Li-Mn-O rock-salt space, with a focus on the thermodynamics of the...

Synchronized states in a ring of dissipatively coupled harmonic oscillators

Moreno JN
Wächtler CW
Eisfeld A
2024

The question under which conditions oscillators with slightly different frequencies synchronize appears in various settings. We consider the case of a finite number of harmonic oscillators arranged on a ring, with bilinear, dissipative nearest-neighbor coupling. We show that by tuning the gain and loss appropriately, stable synchronized dynamics may be achieved. These findings are interpreted using the complex eigenvalues and eigenvectors of the non-Hermitian matrix describing the dynamics of the system. We provide a complete discussion for the case of two oscillators. Ring sizes...

Engineering interlayer hybridization in van der Waals bilayers

Barré, E.
Dandu, M.
Kundu, S.
Sood, A.
da Jornada, F. H.
Raja, A.
2024

In the decade since the introduction of van der Waals (vdW) heterostructures for designer devices, there has been an abundance of studies on the artificial assembly of vdW heterostructures for light–matter interactions, charge and energy transport, and other condensed matter phenomena. The interlayer interactions or hybridization in these systems non-trivially impact their physical characteristics and are sensitive to a complex set of interdependent, externally tunable parameters. There lacks a coherent perspective on how these external stimuli can be used together to engineer materials...

A static quantum embedding scheme based on coupled cluster theory

Shee, A.
Faulstich, F. M.
Whaley, K. B.
Lin, L.
Head-Gordon, M.
2024

We develop a static quantum embedding scheme that utilizes different levels of approximations to coupled cluster (CC) theory for an active fragment region and its environment. To reduce the computational cost, we solve the local fragment problem using a high-level CC method and address the environment problem with a lower-level Møller–Plesset (MP) perturbative method. This embedding approach inherits many conceptual developments from the hybrid second-order Møller–Plesset (MP2) and CC works by Nooijen [J. Chem. Phys. 111, 10815 (1999)] and Bochevarov and Sherrill [J. Chem....

Evaluating Material Design Principles for Calcium-Ion Mobility in Intercalation Cathodes

Kim, J.
Sari, D.
Chen, Q.
Ceder, G.
Persson, K. A.
2024

Multivalent-ion batteries offer an alternative to Li-based technologies, with the potential for greater sustainability, improved safety, and higher energy density, primarily due to their rechargeable system featuring a passivating metal anode. Although a system based on the Ca2+/Ca couple is particularly attractive given the low electrochemical plating potential of Ca2+, the remaining challenge for a viable rechargeable Ca battery is to identify Ca cathodes with fast ion transport. In this work, a high-throughput computational pipeline is adapted to (1) discover...

The ab initio non-crystalline structure database: empowering machine learning to decode diffusivity

Zheng, H.
Sivonxay, E.
Christensen, R.
Gallant, M.
Luo, Z.
McDermott, M.
Huck, P.
Smedskjær, M. M.
Persson, K. A.
2024

Non-crystalline materials exhibit unique properties that make them suitable for various applications in science and technology, ranging from optical and electronic devices and solid-state batteries to protective coatings. However, data-driven exploration and design of non-crystalline materials is hampered by the absence of a comprehensive database covering a broad chemical space. In this work, we present the largest computed non-crystalline structure database to date, generated from systematic and accurate ab initio molecular dynamics (AIMD) calculations. We also show how the database can...

A Cellular Automaton Simulation for Predicting Phase Evolution in Solid-State Reactions

Gallant, M. C.
McDermott, M. J.
Li, B.
Persson, K. A.
2024

New computational tools for solid-state synthesis recipe design are needed in order to accelerate the experimental realization of novel functional materials proposed by high-throughput materials discovery workflows. This work contributes a cellular automaton simulation framework for predicting the time-dependent evolution of intermediate and product phases during solid-state reactions as a function of precursor choice and amount, reaction atmosphere, and heating profile. The simulation captures the effects of reactant particle spatial distribution, particle melting, and reaction atmosphere...

A dynamically bare metal interface enables reversible magnesium electrodeposition at 50 mAh cm2

Guha, R. D.
Vargas, S.
Spotte-Smith, E. W. C.
Epstein, A. R.
Venetos, M.
Kingsbury, R.
Wen, M.
Blau, S.
Persson, K. A.
2025

Understanding and facilitating pure magnesium nucleation/growth electrodeposition behavior with ultrahigh Coulombic efficiency is complicated by the phenomenon of solid electrolyte interphase (SEI) formation in state-of-the-art, halogen-free magnesium electrolytes. Defining the electrolyte properties necessary to achieve ideal electrodeposition/stripping (E/S) thus remains elusive. Here, we reveal for the first time, rapid magnesium electrodeposition behavior that forms densely aligned, micron-sized thin platelets by establishing a dynamic bare magnesium/electrolyte interface during high-...