Many magnetically frustrated systems exhibit what is known as persistent spin dynamics (PSD) in $\mu$SR experiments, the origin of which has remained mysterious since their discovery in the 1990s. As the temperature is lowered, the muon-spin relaxation rate rises (as would be expected for the slowing-down of spin fluctuations) but this rate then saturates at low temperature, the...
An important theme in magnetism is the understanding of phenomena in reduced dimensions using topology. Examples include excitations such as walls, vortices, merons and skyrmions, which exist in the spin textures of a range of systems [1]. Here we discuss case studies from our recent work, emphasising the ways in which muon site calculations, material simulation and $\mu$SR data can be...
Intrinsic magnetic topological insulators from the MnBi₂Te₄·(Bi₂Te₃)ₙ family have garnered significant attention as versatile platforms capable of hosting a range of exotic quantum states and phenomena, including higher-order topological phases, axion electrodynamics, and the quantum anomalous Hall effect. This tunability arises from manganese–pnictogen intermixing, which is sensitive to...
Electronic correlations lead to heavy quasiparticles in three-dimensional metals, and their collapse can destabilize magnetic moments. It is an open question whether there is an analogous instability in one-dimensional systems, unanswered due to the lack of metallic spin chains. Recently, using neutron scattering, we reported a metallic correlated frustrated spin-1/2 chain compound, Ti4MnBi2...
Spin crossover (SCO) compounds are metal-ligand complexes which can easily switch their internal arrangement of electrons in d-orbitals from paired (low-spin) to unpaired (high-spin), by a minor variation in temperature, pressure, magnetic or electric field, or via irradiation. SCO is observed for some metal-organics containing Fe(II), Fe(III), Mn(III) or Co(II) ions, and the switching is...
Altermagnets are a novel type of magnetic system that has a spin-polarized electric band structure in the absence of a net magnetic moment. Microscopically this arises from two opposite spin sublattices that are connected by a lattice rotational symmetry instead of a simple translation or inversion [1]. A ferromagnetic-like transport response makes these systems particularly interesting for...
Establishing a sustainable society is one of the 21st century’s grand challenges. A key barrier is the efficient harvesting, storage, and use of clean energy. Addressing this requires developing new generations of functional materials and devices with advanced energy and quantum properties, which in turn demands control over matter at the nanometer, atomic, and subatomic scales.
In this...
Sodium ion batteries have been attractive and developed eagerly for practical use as one of post Lithium ion batteries. Battery materials NaCrO$_{2}$ and LiCrO$_2$ share an identical crystal structure: i.e., a two dimensional layered rock-salt type structure. NaCrO$_2$ shows high performance with a large capacity of 200 mAh in charge/discharge cycles, while LiCrO$_2$ has a small capacity in a...
To address carbon dioxide emissions, battery performance must be improved. Lithium-ion batteries (LIBs) dominate the market, but their limited and geographically concentrated resources have prompted research into sodium-ion batteries (NIB) to replace LIBs [1]. At J-PARC, we employed positive muon spin relaxation ($\mu^+$SR) [2] and small-angle neutron scattering (SANS) [3] in hard carbon,...
Palladium metal is known to be formed as palladium hydride PdH x by the penetration of dissociated hydrogen atoms into the crystal lattice in a hydrogen gas atmosphere, and has been studied extensively from the viewpoint of industrial applications as a hydrogen storage material. On the other hand, it is also known to exhibit superconductivity at high hydrogen concentrations at low...
The D-line of the J-PARC MLF MUSE has a pion decay section, which provides access to decay muons in addition to surface muons. The y-superconducting solenoid magnets used in the pion decay section have a large aperture and warm bore, allowing them to guide a wide range of positive and negative muons from high to very low momentum. In addition, the world's highest proton energy of 3 GeV makes...
The current and foreseeable status of the TRIUMF Centre for Molecular and Materials Science experimental facilities will be presented. The new M9A and M9H beam lines will be highlighted ... which provide a high flux surface beam and an arbitrarily spin polarized decay beam respectively.
The MuSIC muon beamline at RCNP, University of Osaka provides a continuous muon beam with the K140 and K400 cyclotron accelerators. The employment of large capture solenoid magnets and a long cylindrical production target facilitates the utilization of high-intensity muon beams. The first muon beam was observed in 2012, and then user experiments were conducted between 2016 and 2019. However,...
A Muon station for sciEnce, technoLOgy and inDustrY (MELODY) project has started construction in the beginning of 2024 at China Spallation Neutron Source (CSNS). A stand-alone target station is designed to produce pions and muons.Three muon beamlines are designed for various applications, including a surface muon beam, a dedicated negative muon beam and one decay muon beamline. A muSR...
Muon microscopes [1-3] under development at J-PARC are reported. The transmission muon microscope (TμM) is an analog of a transmission electron microscope (TEM). By employing the strongest penetration power of muons into materials, the TμM allows us to visualizes the 3-dimensional distribution of electromagnetic field in objects much thicker compare to TEMs. This capability is useful to...
Muon Spin Relaxation measurements at continuous sources have stagnated at a stopped muons rate of 40 kHz and generally require sample sizes of at least 5 mm by 5 mm. Taking advantage of recent developments in pixel detector technology, we successfully implemented a prototype Si-pixel-based muon spin spectrometer at PSI. Unlike scintillator-based systems, this spectrometer utilizes the MuPix11...
Unconventional superconductivity is often referred to as originating from a pairing mechanism different from electron-phonon interactions and connected to an anisotropic superconducting order parameter with sign change of the Cooper pair wavefunction. A common microscopic mechanism discussed in view of high temperature superconductors is the spin-fluctuation mediated pairing where the...
Unconventional superconductors offer pathways to novel technologies and deeper insights into electron correlations in condensed matter. Noncentrosymmetric superconductors, lacking inversion symmetry, exhibit mixed spin singlet/triplet pairing, making them candidates for time-reversal symmetry (TRS) breaking in their superconducting states.
We have identified HfRhGe, a new noncentrosymmetric...
After three decades of research, the symmetry of the superconducting state in Sr2RuO4 is still under strong debate (1). The long time favoured spin-triplet px + i py state is ruled out by NMR experiments (2). However, in general time-reversal-symmetry breaking (TRSB) superconductivity indicates complex two-component order parameters. Probing Sr2RuO4 under uniaxial pressure offers the...
We report the discovery of a remarkably rich phase diagram in the kagome superconductor YRu$_{3}$Si$_{2}$, uncovered through a unique combination of muon spin rotation, magnetotransport, X-ray diffraction, and density functional theory calculations. Our study reveals the emergence of a charge-ordered state with a propagation vector of (1/2, 0, 0), setting a record onset temperature of 800 K...
Muon-Induced X-ray Emission (MIXE) is a non-destructive analytical technique that combines the unique properties of negative muons with high resolution gamma detectors to perform depth-resolved elemental analysis. At PSI, the Germanium Array for Non-destructive Testing (GIANT) instrument leverages a high-intensity continuous muon beam (15–60 MeV/c) to implant muons at tunable depths (µm to cm...
In condensed matter physics, designing and understanding quantum materials has been the key to searching for emergent behavior and phases of matter and opening a pathway to use them for energy relevant technologies [1]. In the context of correlated quantum materials often hosting 4f and 5f electrons [2,3], a variety of intriguing physical phenomena appear and attract great attention due to an...
A quantum spin liquid (QSL) is a long-sought magnetic state in which strong quantum fluctuations prevent magnetic ordering, allowing spin dynamics to persist at very low temperatures. Rare-earth triangular lattice compounds have proven to be a particularly promising platform to study spin liquid behaviours due to their localised f-orbitals and inherent geometric frustration. We present $\mu$SR...
Recently, bulk superconductivity has been observed in the layered nickelates La₃Ni₂O₇ and La₄Ni₃O₁₀ under hydrostatic pressure, with transition temperatures of up to 80 K. At ambient pressure, these compounds exhibit intertwined and non-trivial spin-density wave (SDW) and charge-density wave (CDW) orders.
In this work, we present a detailed investigation [1, 2] of the structural,...
The cuprate superconductor La2-xBaxCuO4 (x=0.125) is a striking example of intertwined electronic orders, where 3D superconductivity is anomalously suppressed, allowing spin and charge stripe order to develop, in a manner consistent with the emergence of a pair-density-wave state.
Understanding this interplay remains a key challenge, highlighting the necessity of external tuning for deeper...
Muon Knight shift measurements are a well-established method for determining pairing symmetries in superconductors, particularly effective for $f$-electron-based heavy fermion superconductors. However, precise measurements remain challenging in $d$-electron-based superconductors such as Sr$_2$RuO$_4$, where the Knight shift is intrinsically an order of magnitude smaller.
In this talk, we...
Superconductors that spontaneously break rotational symmetry in their electronic ground state are called nematic superconductors. Cu$_x$Bi$_2$Se$_3$ and CaSn$_3$ are two notable examples that have been studied extensively. Yet, proving the existence of the nematic superconducting state is challenging. Recent theoretical work predicts that odd-parity nematic SC should exhibit a unique magnetic...
Centrosymmetric GdRu$_2$Si$_2$ exhibits a variety of multi-$Q$ magnetic states as a function of temperature and applied magnetic field, including a square skyrmion-lattice phase. The material’s behaviour is strongly dependent on the direction of the applied field, with different phase diagrams resulting for fields applied parallel or perpendicular to the crystallographic $c$ axis. Using...
Multi-quantum (MQ) spectroscopy allows to selectively probe anisotropic muonium. The principal idea is to resonantly drive MQ spin transitions, for which both the electron and the muon spin flip simultaneously (Fig. 1a). In the high-field limit of the electron spin, such MQ microwave excitations are only possible in presence of hyperfine anisotropy, as demonstrated recently for bond-centered...
The small amount of carbon in steel (<1%), critical in determining its properties, strongly depends on steel production technology. Destructive methods have been generally used to quantify carbon. Still, non-destructive and bulk analysis methods are required from the perspective of quality control in steel production and the analysis of cultural heritages. We propose a novel method of...
Radio-frequency muon spin resonance (RF-µSR) has been used to investigate the temperature dependence of the hyperfine parameters of the 2-Norbornyl radical formed in polycrystalline norbornene. Working at a fixed RF frequency of 170.5MHz, field scans show striking changes in both the resonance line shape and amplitude as the temperature is scanned through the plastic phase, with the signal...
Chirality — the geometric property defining the handedness of an object — is a fundamental concept with broad relevance across scientific disciplines. Recent advances have highlighted the pivotal role of chirality in condensed matter physics, particularly through the emergence of chiral phonons: vibrational excitations that carry angular momentum. These quasiparticles are of great interest due...
The kagome lattice has attracted significant attention in the condensed matter community due to its rich sequence of emergent quantum phases, including chiral charge order, nematicity, superconductivity, and the anomalous Hall effect. Theoretical studies predict that these materials may host unconventional superconducting states, such as chiral superconductivity, making the experimental...
The mineral averievite Cu5V2O10(CsCl) possesses a different structure compared to herbertsmithite and other Cu-based kagome spin liquid candidates. The kagome layers are separated by two spacer layers, instead of one in herbertsmithite, reinforcing the 2D character.
The pristine averievite is known to order magnetically at 24 K due to Cu2+ magnetic interlayers but these can be replaced...
The antiferromagnetic semiconductor MnTe has recently attracted enormous research interest. Among other distinctions, MnTe has significance as a leading example of altermagnetism, a high-performance thermoelectric compound when lightly doped, and a platform for spintronics based on antiferromagnetic domains. Muon spin relaxation/rotation (µSR) studies of MnTe can help provide a more complete...
The manipulation and observation of charge carrier distributions at the interfaces of semiconductor device structures is a fundamental problem in semiconductor physics. Standard electrical characterization techniques, such as deep level transient spectroscopy (DLTS) or capacitance-voltage (CV) measurements, have limited depth resolution and are unsuitable to probe the nanometer scale regions...
Metal-organic frameworks (MOFs) are composed of metal centres connected by organic polytopic ligands. Their high degree of chemical tunability is reflected in a controlled wide variability of the electronic states, among which magnetism. However, the main drawback against the realization of magnetic phases with high critical temperatures is the weak magnetic coupling between the metal centres...
The effect of pressure on an organic material is large due to its flexibility, and various physical states such as metal-insulator transition, spin liquid and superconductivity appear. Therefore, systematic research under pressure is important to understand their electronic or magnetic nature. The organic material, $\lambda$-(BEDSe-TTF)$_2$GaCl$_4$, is a Mott insulator and antiferromagnetic...
CsNiCrF$_6$ is a compound which exhibits multiple coulomb phases: charge ice, displacement ice and spin ice. Having all three of these Coulomb phases ensures that bulk techniques for measuring the dynamics in this compound struggle to grapple with the inherent disorder present [1], and density functional theory calculations on this compound are prohibitively expensive. In this talk, I will...
Critical phenomena at phase transitions in multiferroic materials remain not fully understood, and quantum beams drive the elucidation of the phenomena from the viewpoint of microscopic dynamical properties. BiFeO$_3$ is one of the most promising multiferroic materials with high antiferromagnetic ($T_N$$\sim$650 K) and ferroelectric ($T_C$$\sim$1100 K) transition temperatures [1]. We aim to...
Skyrmion lattices (SkLs) are intriguing vortex-like spin textures with non-trivial topology [1,2]. While they are typically stabilized by antisymmetric interactions in bulk noncentrosymmetric materials, centrosymmetric SkL hosts, such as Gd$_2$PdSi$_3$ [2–4], have recently been discovered. There, both the SkL stabilization mechanism under applied fields and the zero-field ground states (GSs)...
A novel formulation of the strong-collision (SC) model is presented in terms of a "SC" projection operator. This very compact and concise notation is ideally suited for the systematic development of the dynamic time evolution of each isochromat in the static frequency spectrum via, for example, cumulant expansion. The resulting model is compared with a non-trivial case for which the strong...
Muon spin rotation and relaxation spectroscopy is a well established experimental probe used to investigate the properties of a wide range of condensed matter systems. However, beyond the properties revealed directly by the best fit parameters of the experiment, computational methods can effectively quantify the microscopic interactions underlying the experimentally observed signal, thus...
The quantum behavior of light nuclei and other particles in materials challenges classical intuition and introduces novel phenomena. Here we demonstrate that muon spin spectroscopy (μSR) is a powerful tool for exploring the quantum effects of light particles, such as the muon, in condensed matter. The muon’s quantum nature is profoundly influenced by the surrounding, offering a unique probe...
In perovskite Ta oxynitrides $A$TaO$_2$N ($A$=Ba, Sr), a new degree of freedom, $cis/trans$, is introduced by the anion configuration. In these materials, a dielectric constant of about 10$^2$-10$^3$ has been observed at room temperature. However, powder X-ray diffractions show structures such as $Pm\bar{3}m$ and ${I4/mcm}$, which have central symmetry and do not exhibit dielectric...
The bulk heterostructure 6R-TaS$_{2}$ offers a unique platform to study the interplay of charge density waves, superconductivity, and electronic transport anomalies. Notably, nematic Ising superconductivity has been recently proposed, and a hidden order accompanied by a large anomalous Hall effect at $T^{*}$ ${\simeq}$ 35 K has been identified, raising fundamental questions about the nature...
In cubic chiral magnets, Dzyaloshinskii-Moriya (DM) interactions within the chiral crystal structure result in diverse magnetic textures, including skyrmion lattices (SkL) and chiral soliton lattices, which hold promise for spintronic and magnonic devices. Among these, MnSi has been extensively studied due to the SkL formation in the so-called “A-phase” just below Tc.
Recently, it was...
The Phase II upgrade project of the China Spallation Neutron Source (CSNS) includes the construction of a surface muon beam line and a muon spin rotation/relaxation/resonance (μSR) spectrometer, which will be the first μSR spectrometer built in China. Here, we report the conceptual design of the spectrometer, including the detector arrangement, magnets, sample environment (SE) and sample...
The interplay between superconductivity and charge or spin order is a key focus in condensed matter physics, with kagome lattice systems providing unique insights [1-9]. We recently discovered that the kagome superconductor LaRu$_{3}$Si$_{2}$ ($T_{\rm c} \simeq 7$ K) exhibits a characteristic kagome band structure and a hierarchy of charge-order transitions at 400 K and 80 K, as well as an...
The science program of elemental analysis is a rapidly expanding area, with applications ranging from cultural heritage to energy materials to advanced manufacturing. Negative muons are an excellent tool for determining the composition of a material, non-destructively, as a function of depth. EVA (Elemental, Visualisation and Analysis) is a new software package that is user-friendly and...
The current beta-NMR/beta-NQR spectrometers in ISAC-1 at TRIUMF constitute a unique research tool, enabling spin polarised ions (typically 8Li+) to be controllably implanted at a depth of between 5 – 200 nm within a material for investigations of thin films and artificial heterostructures. This involves decelerating 8Li+ beams through the generation of a “hill” in the electrostatic potential...
Internal nuclear magnetic fields in various battery materials have been predicted using density functional theory (DFT) calculations to interpret the $\mu^+$SR results, particularly for identifying the diffusing species responsible for the dynamic behavior observed. In materials where Li$^+$ and Na$^+$ ions are mobile, these cations readily change positions to minimize electrostatic repulsion...
Muonic x-ray has been used for an elemental analysis in various research fields. We have applied this technique to detecting metallic Li, which increases the risk to safety in a Li-ion battery. In our study, we found that metallic Li on the graphite anode can be detected with high sensitivity using muonic x-rays while less muon is captured by Li atoms in the anode.
Since metallic Li is...
The value of the nuclear charge radius depends on features of the nuclear structure such as the nuclear charge distribution, ρ, which has been systematically measured for almost all stable nuclei.
The nuclear charge radius can be mathematically defined using ρ, which in turn can be deduced from the X-ray transition energies of a muonic atom. The binding energy of the muonic atom is...
MnGe is a B20 cubic magnetic material observed to host nanoscale topological spin textures. Previous measurements by bulk µSR and small-angle neutron scattering have shown a 3-6 nm helimagnetic state below 200K and a possible 3D skyrmion lattice [1-3]. To further study this material, we have grown high quality crystalline MnGe thin films. With thickness of only a few helical wavelengths,...
GdNi$_4$B is currently one of the optimal magnetocaloric materials for hydrogen liquefaction, but the exact theoretical causes for that are unknown. GdNi$_4$B is a metallic compound exhibiting a ferromagnetic transition at around 50 K, below which they work as a magnetic refrigeration material. Therefore, their ferromagnetic structures should play a key role to determine their optimal magnetic...
Equilateral spin triangles are pivotal in quantum magnetism to explore frustration, spin–electric coupling, and multiferroic ordering. Achieving ideal triangular spin networks is difficult due to structural distortions, but the organic compound TNN·CH3CN overcomes these limitations with isotropic spins free from Jahn–Teller effects, enabling uniform exchange interactions and making it an...
A field-induced quantum spin liquid (QSL) state is an extraordinary phenomenon, hitherto unobserved in metallic frustrated compounds. CePdAl (CPA), a magnetically frustrated metallic compound with a kagome lattice, presents a unique opportunity to explore this phenomenon~\cite{Kitazawa1994}. Recent bulk measurements have revealed intriguing magnetic states in CPA when a magnetic field is...
By definition, properties of the S (superconducting) state are determined by Cooper pairs (CP). The pairs' mobility allows them to organize into a perfectly ordered lattice of microwhirls (MW) formed by the field induced currents in CPs, thereby reducing entropy of the pairs’ ensemble down to zero. The latter entails zero temperature of the ordered CPs, one of the consequences of which is zero...
The μSR experiment has been used to measure diffusion coefficients and activation energies of ions in cathode materials such as LiCoO2. [1] However, direct determination can be challenging due to the use of models such as the Kubo-Toyabe dynamic function, as well as difficulties in distinguishing muon diffusion itself from Li+ diffusion at high temperatures.
First principles calculations...
Muonic X-ray Emission Spectroscopy is a non-destructive method of elemental analysis, which has recently been adopted several fields, such as cultural heritage. It is desirable to have a robust way of computationally modelling these experiments, to allow for simpler and more systematic identification of elemental X-ray intensities, particularly in samples consisting of multiple elements....
Muon spin relaxation has been very successfully used to observe the dynamics in a range of materials, and electronic dynamics typically manifest themselves by showing a muon spin relaxation function which decays exponentially with time, with the rate of decay being related to the field autocorrelation function which can then be used to extract the dynamical parameters of the system [1]....
One of the key challenges in performing experiments is knowing which temperatures and applied fields to measure at, and how many statistics should be measured at each temperature/field combination. We have recently developed a technique which uses Fisher information which, for a given muon asymmetry function, can analytically calculate the number of muon statistics required to have an error of...
The standard interpretation of superconductivity (S) is based on the London theory (LT) with minor modifications adopted in the GL and BCS. In all theories the sample bulk is totally inert and microscopic parameters of the S state can be obtained exclusively from the surface properties, i.e., the penetration depth $\lambda$ and the induction profile B vs depth z. Herewith, $B(z)$ is or close...
Battery materials can undergo a series of structural phase transitions during cycling that significantly change the ionic diffusion. In-operando $\mu$SR measurements provide a powerful new tool to investigate the ionic diffusion in these intermediate phases that affect both the performance and longevity of batteries.
Here we report in-operando $\mu$SR measurements of the battery...
AV$_3$Sb$_5$ (A = K, Cs,and Rb) V-based kagome metals have attracted significant attention owing to the intricate interplay between electronic correlations and nontrivial band topology, including features such as flat bands and van Hove singularities [1,2]. These systems host intertwined electronic instabilities [3], leading to a complex phase diagram between the charge density wave...
Hydrogen is known to degrade the performance of structural materials, a phenomenon commonly referred to as "hydrogen embrittlement". Hydrogen embrittlement is a well-known phenomenon in high strength materials and is responsible for subcritical crack growth in the material, fracture initiation and catastrophic failure with subsequent loss of mechanical properties such as ductility, toughness...
The performance of superconducting cavities in particle accelerators is limited by magnetic flux behavior in the near-surface region, where radiofrequency currents flow. Muon spin rotation (μSR) and beta-detected nuclear magnetic resonance (β-NMR) are uniquely suited to investigate this regime, offering access to local magnetic properties with depth resolution on the nanometer scale. This...
Conventional μSR lacks external control over local muon–spin interactions; to overcome this limitation, we employed pulsed RF techniques to manipulate spin populations in muon-coupled fluoride systems at precisely controlled times after muon implantation, utilizing the ISIS pulsed muon beamline—well suited for such experiments. In ionic fluoride insulators, implanted μ$^+$ forms an F–μ–F...
The magnetic excitation spectrum in a material of interest is governed by the interactions between spins within the lattice. Muon spin relaxation, beta detected nuclear magnetic resonance and the complementary technique of inelastic neutron scattering, among others, yield unique knowledge of the dynamic response of the system. However, the nature of the excitation spectrum at low energies...
Super-MuSR is a project to upgrade the MuSR beamline at ISIS to significantly increase its resolution and counting rate as part of the ISIS Endeavour programme of new and upgraded instruments. Here we report on project progress and component test results.
The beamline upgrade will add pulse slicing and spin rotation capabilities that increase the time resolution by a factor of ten and...
We present a study of the normal-state and superconducting properties of thin-film $\mathrm{Nb_{1-x}Ti_{x}N}$ using depth-resolved $^8$Li $\beta$-detected nuclear magnetic resonance ($\beta$-NMR). Spin-polarized $^8$Li$^{+}$ ions were implanted ~21 nm into a Nb$_{0.75}$Ti$_{0.25}$N(91 nm)/AlN(4 nm)/Nb sample, with their NMR response recorded at temperatures between 4.6 K to 270 K under a 4.1 T...
CaSb2 has been identified as a topological semimetal [1] and a bulk superconductor[2,3]. We investigate the superconducting state and the spontaneous magnetism using muon spin-relaxation (µSR) [4]. Zero-field muon relaxation shows little temperature dependence when the muon-spin is parallel to the c∗-axis, while an increase in relaxation appears below 1 K when the muon-spin is parallel to the...
The objective of the FAMU experiment is to carry out a precision measurement of the muonic hydrogen ground state hyperfine splitting (1S-hfs), with an unprecedented accuracy of the order of $10^{-5}$. This measurement would enable to extract the Zemach radius of the proton with an accuracy better than 1%, which will give precise insights on the structure of the proton, and play a crucial role...
The fineness and quality of a state’s coinage is often used as a proxy for its fiscal health, meaning the purity and chemical composition of coins are of real historical interest. Sampling of such objects is often at the surface or near-surface, but, in ancient coinages, these areas can be unrepresentative of the bulk alloy. Investigations on Roman gold and silver coinage using negative muons...
Copper-exchanged zeolites have emerged as promising catalysts for the direct conversion of methane to methanol, yet the precise nature and dynamics of the active copper species remain elusive. In this study, we apply muon spin spectroscopy (µSR) to investigate local magnetic and electronic environments in Cu-loaded SSZ-13 zeolites, a technique uniquely sensitive to "slow" and local dynamic...
Fe$_3$GeTe$_2$ is a quasi-2D itinerant ferromagnet with a Van-der-Waals layered structure that exhibits substantial magnetic anisotropy. In bulk samples, this material becomes magnetically ordered below 200 K, although the low-temperature magnetic state for pure samples is debated, with some data suggesting a succession of two similar ferromagnetic states, and some suggesting a transition...
LiNi$_{0.8}$Mn$_{0.1}$Co$_{0.1}$O$_2$, commonly known as NMC811, is widely used as a cathode material in Li-ion batteries for electric vehicles due to its high energy density. Despite this, NMC811 and other Ni-rich layered cathode materials suffer from poor cycle life when compared to their lower Ni-containing analogues. This is caused by mechanical stress induced by anisotropic evolution of...
In muon spin rotation/relaxation ($\mu$SR) experiment, the time evolution of muon spin polarization, $P(t)$, is analyzed to evaluate the internal magnetic fields and their temporal fluctuations sensed by the muons at their stopping sites. In conventional data analysis, a phenomenological model for $P(t)$—typically based on general spin relaxation theory (e.g. that by Kubo and Toyabe) —is used...
