Ordering and Defect Cloaking in Nonreciprocal Lattice XY Models.

We present a detailed analytical and numerical examination, on square and triangular lattices, of the nonreciprocal planar spin model introduced in Dadhichi et al. [Phys. Rev.

Time-dependent trajectory of a one-dimensional Gaussian non-Markovian observable does not reveal its nonequilibrium character.

When analyzing experimental or simulation time-series data, the question arises whether it is possible to tell from the mere observation of the time-dependent trajectory of a one-dimensional observable whether the system is in equilibrium or not. We here consider the nonequilibrium version of the generalized Langevin equation for a Gaussian non-Markovian observable and show that (i) the multipoint joint distribution solely depends on the two-point correlation function and that (ii) for any nonequilibrium process an equilibrium process with uniquely determined parameters can be found that produces the same two-point correlation function. Since the multipoint joint distribution completely characterizes the dynamics of an observable, we conclude that the nonequilibrium character of a system, in contrast to its non-Markovianity, cannot be read off from the one-dimensional trajectory of a Gaussian observable.

Nucleobase identification using two-dimensional cobalt telluride.

To facilitate the field of biomedical engineering, rapid DNA sequencing utilising two-dimensional materials (2D) holds enormous significance. Here, the interaction of the 2D-cobalt telluride (2D-CoTe) with all four mono-nucleobase single-stranded DNAs (ssDNAs) has been studied using Raman spectroscopy. The Raman spectra illustrate that the guanine and the adenine bases have interacted strongly, though thymine and cytosine do not show strong interaction.

Machine-learning study of phase transitions in Ising, Blume-Capel, and Ising-metamagnet models.

We combine machine-learning techniques with Monte Carlo (MC) simulations and finite-size scaling (FSS) to study continuous and first-order phase transitions in Ising, Blume-Capel, and Ising-metamagnet spin models. We go beyond earlier studies that had concentrated on obtaining the correlation-length exponent ν. In particular, we show (a) how to combine neural networks (NNs), trained with data from MC simulations of Ising-type spin models on finite lattices, with FSS to obtain both thermal magnetic exponents y_{t}=1/ν and y_{h}, respectively, at both critical and tricritical points, (b) how to obtain the NN counterpart of two-scale-factor universality at an Ising-type critical point, and (c) how to get FSS at a first-order transition.

Melting of rods on a sphere an intermediate hexatic phase.

We have studied, using molecular dynamics simulations, the pressure-induced melting in a monolayer of soft repulsive spherocylinders whose centers of mass are constrained to move on the surface of a sphere. We show that the orientational degrees of freedom of the spherocylinders exhibit nematic order, whereas the positions of their centers of mass exhibit melting transitions that depend on the radius of the confining spherical surface. Our system presents a unique scenario where the decoupling of the orientational degrees of freedom from the positional degrees of freedom leads to an effectively two-dimensional (2D) crystal-to-liquid transition on a spherical surface.

Unveiling the charge transport blockade in the D2 branch of the photosystem II reaction center.

Photosynthesis, the fundamental process sustaining life on Earth, depends on the photosystem II (PSII) reaction center's ability to initiate the charge transport process. In this study, we have investigated this charge transport process with a focus on the dissimilarity between the two branches of the PSII reaction center, D1 and D2. Utilizing Marcus theory, we have calculated the reorganization energies and activation barriers for all the key steps involved in the charge transport process.

Bulk-Boundary Correspondence of Fractonic Field Theories.

We develop a theory of edge excitations of fractonic systems in two dimensions, and elucidate their connections to bulk transport properties and quantum statistics of bulk excitations. The system we consider has immobile point charges, dipoles constrained to move only along lines perpendicular to their moment, and freely mobile quadrupoles and higher multipoles, realizing a bulk fractonic analog of fractional quantum Hall phases. We demonstrate that a quantized braiding phase between two bulk excitations is obtained only in two cases: when a point quadrupole braids around an immobile point charge, or when two non-orthogonal point dipoles braid with one another.

Temporal coarse graining and elimination of slow and periodic dynamics with the generalized Langevin equation for convolution-time-filtered observables.

By exact projection in phase space, we derive the generalized Langevin equation (GLE) for convolution-time-filtered observables. We employ a general convolution filter that directly acts on arbitrary phase-space observables and can involve low-pass, high-pass, band-pass, and band-stop components. The derived filter GLE has the same form and properties as the ordinary GLE but exhibits modified potential, mass, and memory friction kernel.

Orientation dependence of current blockade in single amino acid translocation through a graphene nanopore.

After the successful commercialization of DNA sequencing using biological nanopores, the next frontier for nanopore technology is protein sequencing, a significantly more complex task. Molecules passing through the solid-state nanopores produce current blockades that correlate linearly with their volume in the simplest model. As thinner membranes provide better volume sensitivity, 2D materials such as graphene and MoS membranes have been explored.

Freezing in flat monolayers of soft spherocylinders.

Lamellar or smectic phases often have an intricate intralamellar structure that remains scarcely understood from a microscopic viewpoint. In this work, we use molecular dynamics simulations to study the effect of volume exclusion on the phase transitions of a flat membrane of soft repulsive spherocylinders. With increasing rod packing, we identify liquid crystal and crystal phases and find that the disorder-order phase transition happens at a universal packing fraction (η ≈ 0.

Onset of Intermittency and Multiscaling in Active Turbulence.

Recent results suggest that highly active, chaotic, nonequilibrium states of living fluids might share much in common with high Reynolds number, inertial turbulence. We now show, by using a hydrodynamical model, the onset of intermittency and the consequent multiscaling of Eulerian and Lagrangian structure functions as a function of the bacterial activity. Our results bridge the worlds of low and high Reynolds number flows as well as open up intriguing possibilities of what makes flows intermittent.

Similar structure but different thermodynamic, dielectric, and frictional properties of confined water in twisted 2D materials: MoS graphene.

Water-based nanofluidic devices, where water is confined in Angstrom scale nanochannels, are widely encountered in nanotechnology. Although it is known that the material of confinement has a significant influence on the properties of confined water, much less is known of the relationship between the structure of nanoconfined water and its properties, impacting the design of nanofluidic devices. We explore the behavior of a confined water monolayer within a bilayer molybdenum disulfide (MoS) structure, comparing its behavior with that within bilayer graphene.

Turbulent cascade arrests and the formation of intermediate-scale condensates.

Energy cascades lie at the heart of the dynamics of turbulent flows. In a recent study of turbulence in fluids with odd viscosity X. M.

Inertia Drives Concentration-Wave Turbulence in Swimmer Suspensions.

We discover an instability mechanism in suspensions of self-propelled particles that does not involve active stress. Instead, it is driven by a subtle interplay of inertia, swimmer motility, and concentration fluctuations, through a crucial time lag between the velocity and the concentration field. The resulting time-persistent state seen in our high-resolution numerical simulations consists of self-sustained waves of concentration and orientation, transiting from regular oscillations to wave turbulence.

Chirality and odd mechanics in active columnar phases.

Chiral active materials display odd dynamical effects in both their elastic and viscous responses. We show that the most symmetric mesophase with 2D odd elasticity in three dimensions is chiral, polar, and columnar, with 2D translational order in the plane perpendicular to the columns and no elastic restoring force for their relative sliding. We derive its hydrodynamic equations from those of a chiral active variant of model H.

Stability and conformation of DNA-hairpin in cylindrical confinement.

We conducted atomistic Molecular Dynamics (MD) simulations of DNA-Hairpin molecules encapsulated within Single-Walled Carbon Nanotubes (SWCNTs) at a temperature of 300 K. Our investigation revealed that the structural integrity of the DNA-Hairpin can be maintained within SWCNTs, provided that the diameter of the SWCNT exceeds a critical threshold value. Conversely, when the SWCNT diameter falls below this critical threshold, the DNA-Hairpin undergoes denaturation, even at a temperature of 300 K.

Thermodynamics of multicolored loop models in three dimensions.

We study order-disorder transitions in three-dimensional multicolored loop models using Monte Carlo simulations. We show that the nature of the transition is intimately related to the nature of the loops. The symmetric loops undergo a first-order phase transition, while the nonsymmetric loops show a second-order transition.

Percolation in a three-dimensional nonsymmetric multicolor loop model.

We conduct Monte Carlo simulations to analyze the percolation transition of a nonsymmetric loop model on a regular three-dimensional lattice. We calculate the critical exponents for the percolation transition of this model. The percolation transition occurs at a temperature that is close to, but not exactly, the thermal critical temperature.

Derivation of the nonequilibrium generalized Langevin equation from a time-dependent many-body Hamiltonian.

It has become standard practice to describe systems that remain far from equilibrium even in their steady state by Langevin equations with colored noise which is chosen independently from the friction contribution. Since these Langevin equations are typically not derived from first-principle Hamiltonian dynamics, it is not clear whether they correspond to physically realizable scenarios. By exact Mori projection in phase space we derive the nonequilibrium generalized Langevin equation (GLE) for an arbitrary phase-space dependent observable A from a generic many-body Hamiltonian with a time-dependent external force h(t) acting on the same observable A.

Twist Angle-Dependent Phonon Hybridization in WSe/WSe Homobilayer.

The emerging moiré superstructure of twisted transition metal dichalcogenides (TMDs) leads to various correlated electronic and optical properties compared to those of twisted bilayer graphene. In such a versatile architecture, phonons can also be renormalized and evolve due to atomic reconstruction, which, in turn, depends on the twist angle. However, observing this reconstruction and its relationship to phonon behavior with conventional, cost-effective imaging methods remains challenging.

Permeability of TB drugs through the mycolic acid monolayer: a tale of two force fields.

Tuberculosis (TB) treatment becomes challenging due to the unique cell wall structure of (M. tb). Among various components of the M.

Emergent Inhomogeneity and Nonlocality in a Graphene Field-Effect Transistor on a Near-Parallel Moiré Superlattice of Transition Metal Dichalcogenides.

At near-parallel orientation, twisted bilayers of transition metal dichalcogenides exhibit interlayer charge transfer-driven out-of-plane ferroelectricity. Here, we report detailed electrical transport in a dual-gated graphene field-effect transistor placed on a 2.1° twisted bilayer WSe.

Data-Driven Approaches to Predict Dendrimer Cytotoxicity.

Dendrimers are employed as functional elements in contrast agents and are proposed as nontoxic vehicles for drug delivery. Toxicity is a property that is to be evaluated for this novel class of bionanomaterials for in vivo applications. The current research is hampered due to the lack of structured data sets for toxicity studies for dendrimers.