In article number 2200055, André Souto, Diogo Cunha, and Mikhail I. Vasilevskiy present a semi-analytical theoretical model which describes the operation of a selective molecular sensor employing a double resonance between a dipole-active molecular vibration, electrically tunable surface plasmons in a periodic structure of graphene nanoribbons, and the incident light in the terahertz-to-infrared range. The model is based on the solution of Maxwell’s equations for the nanoribbon structure deposited on a dielectric substrate with an additional dielectric layer between the bottom gate and the nanoribbons. The thickness of this layer can be adjusted in order to enhance, via constructive interference, the plasmonic resonance (see figure) and, consequently, the sensing platform–analyte coupling. – This article belongs to the Special Section “Mathematical Modelling in Materials Science of Electronic Components” (see Guest Editorial by Nikolai A. Sobolev and Karine K. Abgaryan, article number 2200505).

For complex L1₂ structure alloys, the slip mechanism and the dislocation dissociation modes cannot be accurately described based only on criteria like the unstable and stable stacking-fault energies and their ratio. Further precise investigations are required. In article number 2200211, Zhipeng Wang, Touwen Fan and co-workers apply the 2D Peierls-Nabarro model to simulate the <110>{111} superdislocation dissociation in L1₂-Al₃RE (RE = Er, Tm, Yb, Lu) compounds, revealing three types of dissociation: (i) into two superpartials 1/2<110> (red arrows in top-right image) connecting anti-phase boundary (APB); (ii) four Shockley partials 1/6<112> (blue arrows) corresponding to two complex stacking faults (CSFs) and one APB, and (iii) two super-Shockley partials 1/3<112> (black arrows) bounding superlattice intrinsic stacking fault (SISF).

Herein, the charge density difference of 2H-VS₂/BiFeO₃(0001) interfaces and the band alignment between free-standing 2H-VS₂ monolayer and BiFeO₃(0001) surfaces are discussed.

Wide-gap (Ag,Cu)(In,Ga)Se₂ solar cells are characterized after storage, dry annealing, and light-soaking treatments. Through variation of the depletion width, these treatments induce highly significant changes in the performance of the cells. The absorber stoichiometry is revealed to play an important role, with moderately off-stoichiometric cells exhibiting large changes in short-circuit current and close-stoichiometric cells suffering from open-circuit voltage losses.

The proposed nomogram method is described in detail for nickel spinel–lead zirconate titanate and Terfenol-D–piezoquartz (X-cut) in the low-frequency range and in the region of electromechanical resonance. The results obtained show that the nomogram method, in contrast to the general method, allows a quicker and easier determination of the magnetoelectric voltage coefficients with considerable accuracy.

A solution method is developed to synthesize lead-free Cs₃Sb₂Br₉ microplatelets with regular hexagonal shapes, which exhibit photoluminescence at 420 and 600 nm, when excited at 325 and 532 nm, respectively. During storage, the microplatelets significantly degrade meanwhile the photoluminescence quenches due to the intrinsic instability. As a preliminary exploration, oleic acid-capped Cs₃Sb₂Br₉ microplatelets are synthesized to improve the stability.

The martensitic transformation and magnetocaloric properties of MnNi_0.88GeV_0.12 alloy under ambient pressure and external hydrostatic pressure are studied. The measured phase transition temperature of the sample is near room temperature. The applied hydrostatic pressure makes the phase transition temperature of the alloy move to the low-temperature region, and the entropy change value of the sample increases significantly.

Understanding the physical mechanism of heat dissipation is a matter of increasing concern from the perspective of waste heat management in nanostructure-based devices. The authors investigate the relaxation rate and the cooling power due to acoustic phonon interaction via the deformation potential (including the Thomas–Fermi screening) in disordered bilayer graphene at low temperatures within the impure limit, through the Keldysh technique.

The multiferroic properties of pure and ion-doped BiCrO₃, bulk and thin films, are investigated theoretically. It is shown that pure bulk BiCrO₃ is antiferromagnetic and antiferroelectric. By doping with Ga, Mn, or Ti ion, there appears ferroelectric polarization P, which increases with increasing ion doping concentration. It is found that BiCrO₃ thin films are ferromagnetic and ferroelectric.

The optical spectra of CdSiP₂ and CdSiAs₂ display anisotropy in two directions, with a very slight difference in the static limit in the mBJ-approach. Peaks decrease in energy as one moves from P to As. The optical absorption edge is located at ≈1.18 and 0.82 eV for each. CdSiP₂ and CdSiAs₂ exhibit anisotropic refractive index spectra. The computed optical results indicate that all compounds exhibit optical polarization anisotropy, making them suitable for optoelectronic devices.

This paper includes work regarding density functional theory (DFT) studies undertaken on the 30° and 90° partial dislocations in HgTe, Hg_0.7Cd_0.3Te, and CdTe. The results include the dislocation core structures and energies as well as the impact that these dislocations have on the optoelectronic properties through the density of states.

Herein, the heat capacity of GdBaCuFeO₅ is calculated by using the fitting equation that consists of the contribution from electronic, Debye and Einstein terms. The results agree well with the available literature data. The deviations observed below 30 K can be eliminated by adding the effect of crystalline electric field on the rare earth ions.

K₂GaAgCl₆ and Cs₂GaAgCl₆ reveal a direct bandgap (E _g) of 2.57 and 2.63 eV, respectively, at Γ symmetry points. The negative values of formation enthalpy and a value of tolerance factor (τ) close to unity confirm the stable nature of X₂GaAgCl₆ (X = Cs, K) in cubic phase. The highest peak of optical conductivity is found at 4.74 and 4.93 eV for K₂GaAgCl₆ and Cs₂GaAgCl₆, respectively, and the highest absorption at 7.46 and 7.44 eV. Investigation of elastic, structural, and optical properties shows that the compounds X₂GaAgCl₆ (X = Cs, K) can be potential candidates for optoelectronic applications.

A self-consistent analysis of specific heat in iron-pnictide superconductors is attempted. A pseudogap parameter arising out of multi-orbitals’ Hund's coupling is introduced to investigate the influence of the pseudogap on specific heat (using three-orbital per site model) in iron-pnictide systems like LaOFeAs and hence, it is observed that pseudogap affects specific heat significantly.

Based on the density functional theory (DFT) calculations, Ta₂TlC and Ta₂TlN MAX-phase compounds are investigated. The calculated formation energy, phonon dispersion, and elastic constants reveal that these compounds can be synthesized experimentally. From mechanical properties, the studied compounds show distinct mechanical features. In addition, metallic behavior with ionic bonding is found. Furthermore, an interesting low thermal conductivity is obtained for both studied compounds.

Oxygen plasma treatment is the simplest method for the known graphene energy band modulation process. Herein, oxygen plasma technique is adopted to etch the chemical vapor deposition few-layer graphene film in the low-pressure cavity. The whole process is followed by controlling the time variable to investigate the effect of different etching parameters on the optical properties of few-layer graphene.

The binary rare-earth-based intermetallics Gd₅In₃ and Tb₅In₃ have intriguing magnetic and electronic properties. Both the compounds show multiple magnetic transitions, and are associated with magnetofunctional properties. While Tb₅In₃ shows moderate magnetocaloric effect at around 160 K, Gd₅In₃ shows giant negative magnetoresistance below 10 K.

This study proposes an efficient and rapid energy transfer (ET) mechanism only by mimicking the circular structure of natural photosynthetic light-harvesting (LH) antennae, without spatial and energetic disorders as in natural photosynthetic systems. It is shown that the circular structure enables functional separation of LH and ET, as realized in semiconductor optical devices, leading to efficient and rapid ET.

Herein, the influence of alloying atoms (Gd, Y) on the activation probability of basal and nonbasal <a> slip systems is studied. Different from previous reports, the generalized stacking fault energy of Mg–2Gd, Mg–2Y, and Mg–2Gd–2Y (at%) is studied. It is found that Gd is more effective than Y on the improvement of plasticity.

The generalized stacking-fault energy surface (γ-surface) and the ⟨110⟩{111} superdislocation properties of L1₂-Al₃RE (RE = Er, Tm, Yb, Lu) compounds are first investigated. The present study indicates that the combination of the γ-surface and the modified 2D Peierls–Nabarro model can comprehensively elucidate the complex superdislocation properties and deformation mechanisms of L1₂ structural alloys.

Structural, microscopic, optical, dielectric, ferroelectric, and magnetic properties of Bi_4−x Nd _x (Ti₂Fe)O₁₂ ceramics are studied. The evolution of orthorhombic (up to x = 0.5, further monoclinic structure (with dopant x ≥ 1.0), confirms a structural phase transformation. The optical bandgap increases with dopant substitution whereas ferroelectric hysteresis is retained up to x = 1.0. In conclusion, Nd-substituted Bi₄Ti₂FeO₁₂ exhibits a good multiferroic character.

The second harmonic generation of spherical quantum dots affected by screened Kratzer potential and regulatory factors is studied theoretically. The results show that the screened Kratzer potential parameters and regulatory factors play a key role in the change of the peak value and position of the second harmonic generation coefficient.

Ion-implanted Mg atoms having a Gaussian-shaped depth profile in GaN are annealed at 1300 °C under ultra-high pressure (UHPA). Hydrogen (H) atoms introduced from the UHPA ambient significantly enhance Mg diffusion by forming diffusive Mg–H complexes, resulting in the diffusion mechanism changing from a simple Mg diffusion to Mg–H diffusion after a certain annealing duration.

Reflectance anisotropy spectroscopy (RAS) is suitable to investigate the effect of strain on the electronic properties of 2D-layered materials. It enables to follow in real time the optical/electronic properties during the growth of GaAsBi in molecular beam epitaxy (MBE) and metal–organic vapor pressure epitaxy (MOVPE).

Both thoria ThO₂ and urania, UO₂, adopt the cubic fluorite phase and this is reproduced in theory.

The magnetic hysteresis behavior, local atomic structure, and cation distribution of Fe-substituted metal aluminates, MFe _x Al_2−x O₄ powders (M = Ni²⁺, Cu²⁺, and Zn²⁺) with different Fe³⁺ ion concentrations (x = 0, 0.5, 1.0, 1.5, and 2), are fully studied using a vibrating sample magnetometer and synchrotron extended X-ray absorption fine structure.

Carbon-coated iron-nickel alloy nanoparticles exhibit unique ferromagnetic properties in the face centered cubic (FCC) phase.

Two-line ferrihydrite particles are synthesized. Average particle size is 2 nm. Temperature variation of zero-field-cooled and field-cooled susceptibility in 500 G applied magnetic field bifurcates at 50 K. The field-cooled susceptibility below this temperature is almost temperature independent. Magnetization versus applied magnetic field data at 300 K are analyzed considering particle size distribution.

The authors propose a hybrid metamaterial structure with a complete band gap below 500 Hz, which is subjected to second-order fractal, series fusion, and whether the structure is framed or not to form 8 different structures. The complete band gap of its tandem fusion structure accounts for up to 45.502% in the range of 500 Hz.

An impressive red-emission is realized in Sr₉MnK(PO₄)₇ phosphor via energy transfer between Eu²⁺ and Mn²⁺. The energy transfer process can be boosted by adding charge compensation ions such as Ce³⁺, La³⁺, and Gd³⁺ into Sr₉MnK(PO₄)₇ phosphor.

The effect of carbon, a common impurity element in α-Al₂O₃, on the intrinsic point defects, hydrogen-related defects, hydrogen interactionwith intrinsic point defects, and hydrogen migration behaviors is investigated by first-principles calculations.

The microscopic structure and electronic properties of AlInP(001) surfaces are explored. Surfaces grown by metal–organic vapor-phase epitaxy are covered with a monolayer of buckled phosphorus dimers, where half of the phosphorus atoms are hydrogen saturated. Depending on the surface preparation conditions, further semiconducting dimer structures as well as metal atomic wires may form.