Search NASA⌕ Search

SEARCH · Search NASA

Results for “transition state analogs”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Crystal growth and magnetic structure of ternary silicide Eu Pd 3 Si 2

The hexagonal CaCu 5 –type structure (P6/mmm) is the prototype for more than 100 ternary borides, gallides, and silicides, with general stoichiometry of RTM 3 X 2 (R=lanthanide/alkaline earth; TM=transition metal; X=B, Ga, Si, Ge). Here we report the synthesis, crystal structure, and bulk magnetic properties of polycrystalline and single crystal samples of EuPd 3 Si 2 and its nonmagnetic analog SrPd 3 Si 2 . Both compounds crystallize in the orthorhombic space group symmetry Imma (no. 74, Z = 2, oI12) displaying pseudohexagonal symmetry. Ferromagnetic (FM) order of Eu 2+ at T C1 =78K and a spin-reorientation transition at T C2 =5K appear as distinctive features in bulk magnetization, specific heat, and resistivity/resistance measurements. Neutron powder diffraction measurements on EuPd 3 Si 2 confirm FM order of the Eu 2+ spins below T C1 , with the spins aligned along the a axis below T C2 . Electronic band structure calculations corroborate the crystal structure and the FM state for EuPd 3 Si 2 , with a Pd d–band polarization in the same direction as the Eu 4f polarization, enhancing the observed spin moment.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Prediction of Detonation-Induced Disturbances Propagating Upstream into Inlets of Rotating Detonation Combustors

Disturbances caused by the detonation wave in a rotating detonation combustor (RDC) propagate upstream through the inlet, and can potentially affect and couple to upstream components, such as turbomachinery or isolators. These disturbances can potentially also affect the operation of the RDC itself. By drawing from the analogy of a detonation wave bounded by an inert gas, the pressure disturbances observed upstream of the inlet are explained as the consequence of the passage of an upstream propagating oblique shock. In this study, the pressure rise in the plenum from the oblique shock is measured in an axial air inlet RDC. The speed of the upstream propagating wave is estimated to be moderately above the acoustic speed of the oxidizer in the plenum. The wave propagates into the plenum despite local regions of choking in the inlet. It is estimated that the time it takes a fluid particle to transit from the plenum to the detonation channel through the inlet is much larger than the rotational time of the detonation wave. This implies that a fluid particle experiences multiple shocks prior to entering the detonation channel. The oblique shock propagating upstream through the inlet area change is modeled by leveraging an analogy with a quasi-1D shock wave moving in a variable area duct with mean (incoming) flow. Due to flow expansion along the area change, fluid particles are found to experience stronger shocks in the inlet than in the plenum, thereby creating different thermodynamic states within the fill region as the oxidizer emerges from the inlet.

Feleo, Alexander↗
DOE OSTI2021

2D Ni 0.25 Mn 0.75 O 2 : A high-performance cathode for multivalent ion batteries

Although Li-ion batteries have driven portable energy storage in recent decades, there is increasing concern about their safety, cost, and abundance of constituents. Multivalent ion batteries (MVIBs) have the potential to remedy these issues, but they are limited by the currently known MVIB cathodes, which fail to deliver unanimously favorable voltage, energy density, and diffusion kinetics. Here we used density functional theory (DFT) to model the performance of Li, Na, Mg, Ca, and Al ions when paired with 2D Ni 0.25 Mn 0.75 O 2 , a novel cathode that uses increased layer separation to improve on the kinetics of its 3D analog. Our calculations yielded maximum voltages of 3.38 V for Na and 2.7 V for Ca, outperforming 2D Na x MnO 2 and Na x NiO 2 . Diffusion barriers for Li, Na, and Ca are below 300 meV, comparable to existing battery technology and the endpoint 2D cathodes; meanwhile, Mg and Al have prohibitively high diffusion barriers, implying their incompatibility with this cathode. Lastly, density of states calculations and Bader charge analysis show that the cathode becomes conducting following ion adsorption, which is necessary for high-rate performance. 2D Ni 0.25 Mn 0.75 O 2 maintains performance seen with other 2D transition metal oxides while increasing cathode conductivity, indicating that it is a promising candidate for experimental investigation with Li, Na, and Ca ions.

25 ENERGY STORAGE↗
DOE OSTI2020

Guided Ion Beam and Quantum Chemical Investigation of the Thermochemistry of Thorium Dioxide Cations: Thermodynamic Evidence for Participation of f Orbitals in Bonding

Kinetic energy dependent reactions of ThO + with O 2 are studied using a guided ion beam tandem mass spectrometer. The formation of ThO 2 + in the reaction of ThO + with O 2 is observed to be slightly endothermic and also exhibits two obvious features in the cross section. These kinetic energy dependent cross sections were modeled to determine a 0 K bond dissociation energy of D 0 (OTh + - O) = 4.94 ± 0.06 eV. This value is slightly larger but within experimental uncertainty of less precise previously reported experimental values. The higher energy feature in the ThO 2 + cross section was also analyzed and suggests formation of an excited state of the product ion lying 3.1 ± 0.2 eV above the ground state. Additionally, the thermochemistry of ThO 2 + was explored by quantum chemical calculations, including a full Feller-Peterson-Dixon (FPD) composite approach with correlation contributions up to CCSDT(Q) and four-component spin-orbit corrections, as well as more approximate CCSD(T) calculations including semiempirical estimates of spin-orbit energy contributions. The FPD approach predicts D 0 (OTh + -O) = 4.87 ± 0.04 eV, in good agreement with the experimental value. Analogous FPD results for ThO+, ThO, and ThO 2 are also presented, including ionization energies for both ThO and ThO 2 . The ThO 2 + bond energy is larger than those of its transition metal congeners, TiO 2 + and ZrO 2 + , which can be attributed partially to an actinide contraction, but also to contributions from the participation of f orbitals on thorium that are unavailable to the transition metal systems.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Processing Effects on the Self-Assembly of Brush Block Polymer Photonic Crystals

Here,the self-assembly of poly(dimethylsiloxane)-b-poly(trimethylene carbonate) (PDMS-b-PTMC) bottlebrush block polymers was investigated under different processing conditions. Small-angle X-ray scattering (SAXS) and UV/Visible spectroscopy provided insight into the self-assembly and structure in response to heating and applied pressure. In the absence of applied pressure (i.e., before annealing), the PDMS-b-PTMC bottlebrush block polymers are white solids and adopt small, randomly oriented lamellar grains. Heating the materials to 140 °C in the absence of applied pressure appears to “lock in” the isotropic, short-range-ordered state, preventing the formation of the long-range-ordered lamellar structure responsible for photonic properties. Applying modest anisotropic pressure (3 psi) between parallel plates at ambient temperature orients the short-range lamellar grains; however, applied pressure alone does not produce long-range order. Only when the bottlebrush block polymers were heated (>100 °C) under modest pressure (3 psi) were long-range-ordered photonic crystals formed. Analysis of the SAXS data motivated analogies to liquid crystals and revealed the potential self-assembly pathway. These results provide insight into the structure and self-assembly of bottlebrush block polymers with low glass transition temperature side chains in response to different processing conditions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

30S subunit recognition and G1405 modification by the aminoglycoside-resistance 16S ribosomal RNA methyltransferase RmtC

Acquired ribosomal RNA (rRNA) methylation has emerged as a significant mechanism of aminoglycoside resistance in pathogenic bacterial infections. Modification of a single nucleotide in the ribosome decoding center by the aminoglycoside-resistance 16S rRNA (m 7 G1405) methyltransferases effectively blocks the action of all 4,6-deoxystreptamine ring-containing aminoglycosides, including the latest generation of drugs. To define the molecular basis of 30S subunit recognition and G1405 modification by these enzymes, we used a S-adenosyl-L-methionine analog to trap the complex in a postcatalytic state to enable determination of a global 3.0 Å cryo-electron microscopy structure of the m 7 G1405 methyltransferase RmtC bound to the mature Escherichia coli 30S ribosomal subunit. This structure, together with functional analyses of RmtC variants, identifies the RmtC N-terminal domain as critical for recognition and docking of the enzyme on a conserved 16S rRNA tertiary surface adjacent to G1405 in 16S rRNA helix 44 (h44). To access the G1405 N7 position for modification, a collection of residues across one surface of RmtC, including a loop that undergoes a disorder-to order transition upon 30S subunit binding, induces significant distortion of h44. This distortion flips G1405 into the enzyme active site where it is positioned for modification by two almost universally conserved RmtC residues. Further, these studies expand our understanding of ribosome recognition by rRNA modification enzymes and present a more complete structural basis for future development of strategies to inhibit m 7 G1405 modification to resensitize bacterial pathogens to aminoglycosides.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS2010

Thermal Properties of Lunar Regolith Simulants

Various high temperature chemical processes have been developed to extract oxygen and metals from lunar regolith. These processes are tested using terrestrial analogues of the regolith. But all practical terrestrial analogs contain H2O and/or OH-, the presence of which has substantial impact on important system behaviors. We have undertaken studies of lunar regolith simulants to determine the limits of the simulants to validate key components for human survivability during sustained presence on the Moon. Differential Thermal Analysis (DTA) yields information on phase transitions and melting temperatures. Thermo-Gravimetric Analysis (TGA) with Fourier Transform Infrared (FTIR) analysis provides information on evolved gas species and their evolution temperature profiles. The DTA and TGA studies included JSC-1A fine (Johnson Space Center Mare Type 1A simulant), NU-LHT-2M (National Aeronautics and Space Administration (NASA)-- United States Geological Survey (USGS)--Lunar Highlands Type 2M simulant) and its proposed feedstocks: anorthosite; dunite; high quality (HQ) glass and the norite from which HQ glass is produced. As an example, the DTA and TGA profiles for anorthosite follow. The DTA indicates exothermic transitions at 355 and 490 C and endothermic transitions at 970 and 1235 C. Below the 355 C transition, water is lost accounting for approximately 0.1 percent mass loss. Just above 490 C a second type of water is lost, presumably bound in lattices of secondary minerals along with other volatile oxides. Limited TGA-FTIR data is available at the time of this writing. For JSC-1A fine, the TGA-FTIR indicates at least two kinds of water are evolved in the 100 to 500 and the 700 to 900 C ranges. Evolution of carbon dioxide types occurs in the 250 to 545, 545 to 705, and 705 to 985 C ranges. Geologically, the results are consistent with the evolution of "water" in its several forms, CO2 from break down of secondary carbonates and magmatic, dissolved gas and glass recrystallization

Street, Kenneth W., Jr.↗
DOE OSTI2020

Periodic Eruptive Variability of the Isolated Pre-main-sequence Star V347 Aurigae

V347 Aurigae is associated with the small dark cloud L1438 and appears to be an isolated pre-main-sequence star located at distance d ≈ 200 pc. Multi-epoch, archival photometry reveals periodic brightness variations with amplitude V ≈ 2.0 mag occurring on timescales of ~160 days that have persisted for decades. Regular-cadence, optical imaging of the source with the Zwicky Transient Facility shows that a small reflection nebula illuminated by V347 Aur also fluctuates in brightness, at times fading completely. Multi-epoch, Keck/HIRES data suggests the presence of two distinct spectral components: a prominent emission-line-dominated spectrum with a heavily veiled continuum correlated with the bright photometric state, and an M-type absorption line spectrum associated with quiescence. All spectra exhibit strong Balmer and He i line emission, consistent with accretion, as well as high velocity emission arising from the forbidden transitions of [O i], [N ii], and [S ii] that are generally associated with collimated jets and disk winds. There is no evidence in existing high-dispersion spectroscopy or high-resolution imaging for binarity of V347 Aur. The repeating outburst events are possibly linked to accretion instabilities induced by an undetected companion or a structure within the circumstellar disk that periodically increases the mass accretion rate. V347 Aur is perhaps analogous to an EXor-type variable, though more regularly recurring.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

Nature of Excitons and Their Ligand-Mediated Delocalization in Nickel Dihalide Charge-Transfer Insulators

The fundamental optical excitations of correlated transition-metal compounds are typically identified with multielectronic transitions localized at the transition-metal site, such as d d transitions. In this vein, intense interest has surrounded the appearance of sharp, below-band-gap optical transitions, i.e., excitons, within the magnetic phase of correlated Ni 2 + van der Waals magnets. The interplay of magnetic and charge-transfer insulating ground states in Ni 2 + systems raises intriguing questions on the roles of long-range magnetic order and of metal-ligand charge transfer in the exciton nature, which inspired microscopic descriptions beyond typical d d excitations. Here we study the impact of charge transfer and magnetic order on the excitation spectrum of the nickel dihalides ( Ni X 2 , X = Cl , Br, and I) using Ni- L 3 edge resonant inelastic x-ray scattering (RIXS). In all compounds, we detect sharp excitations, analogous to the recently reported excitons, and assign them to spin-singlet multiplets of octahedrally coordinated Ni 2 + stabilized by intra-atomic Hund’s exchange. Additionally, we demonstrate that these excitons are dispersive using momentum-resolved RIXS. Our data evidence a ligand-mediated multiplet dispersion, which is tuned by the charge-transfer gap and independent of the presence of long-range magnetic order. This reveals the mechanisms governing nonlocal interactions of on-site d d excitations with the surrounding crystal or magnetic structure, in analogy to ground-state superexchange. These measurements thus establish the roles of magnetic order, self-doped ligand holes, and intersite-coupling mechanisms for the properties of d d excitations in charge-transfer insulators. Published by the American Physical Society 2024

2-dimensional systems↗
DOE OSTI2024

Deciphering Charge Transfer Processes in Transition Metal Complexes from the Perspective of Ultrafast Electronic and Nuclear Motions

Chemical transformations in charge transfer states result from the interplay between electronic dynamics and nuclear reorganization along excited-state trajectories. Here, in this study, we investigate the ultrafast structural dynamics following photoinduced electron transfer from the metal-metal-to-ligand charge transfer state of an electron donor, a Pt dimer complex, to a covalently linked electron acceptor group using ultrafast time-resolved wide-angle X-ray scattering and optical transient absorption spectroscopy methods to disentangle the interdependence of the excited-state electronic and nuclear dynamics. Following photoexcitation, Pt-Pt bond formation and contraction takes up to 1 ps, much slower than the corresponding process in analogous complexes without electron acceptor groups. Because the Pt-Pt distance change is slow with respect to excited-state electron transfer, it can affect the rate of electron transfer. These results have potential impacts on controlling electron transfer rates via structural alterations to the electron donor group, tuning the charge transfer driving force.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Three-state nematicity in the triangular lattice antiferromagnet Fe 1/3 NbS 2

Nematic order is the breaking of rotational symmetry in the presence of translational invariance. While originally defined in the context of liquid crystals, the concept of nematic order has arisen in crystalline matter with discrete rotational symmetry, most prominently in the tetragonal Fe-based superconductors where the parent state is four-fold symmetric. In this case the nematic director takes on only two directions, and the order parameter in such 'Ising-nematic' systems is a simple scalar. In this study, using a spatially resolved optical polarimetry technique, we show that a qualitatively distinct nematic state arises in the triangular lattice antiferromagnet Fe 1/3 NbS 2 . The crucial difference is that the nematic order on the triangular lattice is a Z 3 or three-state Potts-nematic order parameter. As a consequence, the anisotropy axes of response functions such as the resistivity tensor can be continuously reoriented by external perturbations. This discovery lays the groundwork for devices that exploit analogies with nematic liquid crystals.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Piezosuperconductivity: Novel effects in noncentrosymmetric superconductors

Here we study effects in noncentrosymmetric superconductors arising from their unique coupling of Cooper-pair condensate and elasticity. We show that although the much discussed Lifshitz coupling is not observable in a uniform bulk state, it strikingly endows dislocations with a fractional magnetic flux. We also predict a generation of voltage-free strain by a DC current in a P- and T-breaking Josephson junction. Viewing superconductors through the lens of higher-form symmetries we identify the Lifshitz coupling as a chemical potential for the approximately conserved winding number, drawing an analogy with pyroelectric insulators.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Probing the Potential Energy Profile of the I + (H 2 O) 3 → HI + (H 2 O) 2 OH Forward and Reverse Reactions: High Level CCSD(T) Studies with Spin-Orbit Coupling Included

Three different pathways for the atomic iodine plus water trimer reaction I + (H 2 O) 3 → HI + (H 2 O) 2 OH were preliminarily examined by the DFT-MPW1K method. Related to previous predictions for the F/Cl/Br + (H 2 O) 3 reactions, three pathways for the I + (H 2 O) 3 reaction are linked in terms of geometry and energetics. To legitimize the results, the “gold standard” CCSD(T) method was employed to investigate the lowest-lying pathway with the correlation-consistent polarized valence basis set up to cc-pVQZ(-PP). According to the CCSD(T)/cc-pVQZ(-PP)//CCSD(T)/cc-pVTZ(-PP) results, the I + (H 2 O) 3 → HI + (H 2 O) 2 OH reaction is predicted to be endothermic by 47.0 kcal mol -1 . The submerged transition state is predicted to lie 43.7 kcal mol -1 above the separated reactants. The I···(H 2 O) 3 entrance complex lies below the separated reactants by 4.1 kcal mol -1 , and spin-orbit coupling has a significant impact on this dissociation energy. The HI···(H 2 O) 2 OH exit complex is bound by 4.3 kcal mol -1 in relation to the separated products. Compared with simpler I + (H 2 O) 2 and I + H 2 O reactions, the I + (H 2 O) 3 reaction is energetically between them in general. It is speculated that the reaction between the iodine atom and the larger water clusters may be energetically analogous to the I + (H 2 O) 3 reaction. The iodine reaction I + (H 2 O) 3 is connected with the analogous valence isoelectronic bromine/chlorine reactions Br/Cl + (H 2 O) 3 but much different from the F + (H 2 O) 3 reaction. Significant difference with other halogen systems, especially for barrier heights, are seen for the iodine systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

A structural and electrochemical study of perfluoropolyether-poly(ethylene oxide) solid polymer electrolytes

Solid polymer electrolytes offer attractive safety, processability, and interfacial adhesion for enabling high–energy solid-state lithium batteries, but they are often limited by narrow oxidative stability windows and low lithium-ion transference numbers. In an attempt to broaden the electrochemical stability window and increase lithium-ion transference number of poly(ethylene oxide) (PEO)-based solid polymer electrolytes, we produce an optically clear, crosslinked membrane of PEO and perfluoropolyether (PFPE) using a mixed solvent method and subsequently infuse the membrane with a lithium salt. Structural and thermal analyses reveal nanoscale phase separation between fluorocarbon and hydrocarbon domains with characteristic spacings of 7–8 nm and an elevated glass transition for the hydrocarbon phase. Consistent with this, PFPE-containing membranes exhibit substantially lower ionic conductivity than PEO analogs (dry and plasticized). The transference number and electrochemical stability are similar to pure PEO. These results demonstrate that fluorination implemented as segregated nanoscale domains does not deliver the anticipated transport or stability benefits; instead, phase separation increases tortuosity and suppresses hydrocarbon-phase dynamics. The work underscores the importance of fluorine placement and morphology control, guiding the design of partially fluorinated solid polymer electrolytes toward architectures that avoid detrimental nanoscale phase separation.

Carden, Peyton [ORNL] (ORCID:0000000162296538)↗
NASA NTRS2013

Direct Numerical Simulation of Transition in a Swept-Wing Boundary Layer

Direct numerical simulation (DNS) is performed to examine laminar to turbulent transition due to high-frequency secondary instability of stationary crossflow vortices in a subsonic swept-wing boundary layer for a realistic natural-laminar-flow airfoil configuration. The secondary instability is introduced via inflow forcing derived from a two-dimensional, partial-differential-equation based eigenvalue computation; and the mode selected for forcing corresponds to the most amplified secondary instability mode which, in this case, derives a majority of its growth from energy production mechanisms associated with the wall-normal shear of the stationary basic state. Both the growth of the secondary instability wave and the resulting onset of laminar-turbulent transition are captured within the DNS computations. The growth of the secondary instability wave in the DNS solution compares well with linear secondary instability theory when the amplitude is small; the linear growth is followed by a region of reduced growth resulting from nonlinear effects before an explosive onset of laminar breakdown to turbulence. The peak fluctuations are concentrated near the boundary layer edge during the initial stage of transition, but rapidly propagates towards the surface during the process of laminar breakdown. Both time-averaged statistics and flow visualization based on the DNS reveal a sawtooth transition pattern that is analogous to previously documented surface flow visualizations of transition due to stationary crossflow instability. The memory of the stationary crossflow vortex is found to persist through the transition zone and well beyond the location of the maximum skin friction.

Duan, Lian↗
NASA NTRS2005

Bidirectional Classical Stochastic Processes with Measurements and Feedback

A measurement on a quantum system is said to cause the "collapse" of the quantum state vector or density matrix. An analogous collapse occurs with measurements on a classical stochastic process. This paper addresses the question of describing the response of a classical stochastic process when there is feedback from the output of a measurement to the input, and is intended to give a model for quantum-mechanical processes that occur along a space-like reaction coordinate. The classical system can be thought of in physical terms as two counterflowing probability streams, which stochastically exchange probability currents in a way that the net probability current, and hence the overall probability, suitably interpreted, is conserved. The proposed formalism extends the . mathematics of those stochastic processes describable with linear, single-step, unidirectional transition probabilities, known as Markov chains and stochastic matrices. It is shown that a certain rearrangement and combination of the input and output of two stochastic matrices of the same order yields another matrix of the same type. Each measurement causes the partial collapse of the probability current distribution in the midst of such a process, giving rise to calculable, but non-Markov, values for the ensuing modification of the system's output probability distribution. The paper concludes with an analysis of a classical probabilistic version of the so-called grandfather paradox.

Hahne, G. E.↗
DOE OSTI2021

Excitonic density wave and spin-valley superfluid in bilayer transition metal dichalcogenide

Artificial moiré superlattices in 2 d van der Waals heterostructures are a new venue for realizing and controlling correlated electronic phenomena. Recently, twisted bilayer WSe 2 emerged as a new robust moiré system hosting a correlated insulator at moiré half-filling over a range of twist angle. In this work, we present a theory of this insulating state as an excitonic density wave due to intervalley electron–hole pairing. We show that exciton condensation is strongly enhanced by a van Hove singularity near the Fermi level. Our theory explains the remarkable sensitivity of the insulating gap to the vertical electric field. In contrast, the gap is weakly reduced by a perpendicular magnetic field, with quadratic dependence at low field. The different responses to electric and magnetic field can be understood in terms of pair-breaking versus non-pair-breaking effects in a BCS analog of the system. We further predict superfluid spin transport in this electrical insulator, which can be detected by optical spin injection and spatial-temporal imaging.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2025

Magnetically tuned metal-insulator transition in LaAlO 3 /SrTiO 3 nanowire arrays

A wide family of two-dimensional (2D) systems, including stripe-phase superconductors, sliding Luttinger liquids, and anisotropic 2D materials, can be modeled by an array of coupled one-dimensional (1D) electron channels or nanowire arrays. Here we report experiments in arrays of conducting nanowires with gate and field tunable interwire coupling, that are programmed at the LaAlO 3 /SrTiO 3 interface. We find a magnetically tuned metal-to-insulator transition in which the transverse resistance of the nanowire array increases by up to four orders of magnitude, which can be further tuned with a gate voltage. To explain this behavior, we develop a minimal model of a coupled two-wire system where a Wenzel-Kramers-Brillouin-based approach is used to estimate the transverse tunneling conductance. We demonstrate the existence of distinct conductance features and highlight the crucial role played by the field dependence of the interwire potential barrier on transport properties. Since our model makes minimal assumptions, we expect our predictions to hold for a wide class of coupled 1D systems. The nanowire arrays can serve as model systems to understand the origin of exotic behavior in correlated materials via analog quantum simulation.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗