Journal of Applied Physics

This study investigates the nanoscale conductivity of encapsulated monolayer graphene at temperatures down to 5 K and magnetic fields of up to 1 T. We use the scattering-type scanning near-field optical microscopy technique to probe magnetic-field-dependent responses from graphene close to charge neutrality in the terahertz spectral region. We observe the near-perfect high-q reflector behavior of…

Photoluminescence blinking is a major drawback of semiconductor nanoparticle-based single-photon emitters. Here, we present a novel work on the theoretical analysis of the blinking mechanism in zinc oxide nanoparticles (ZnO NPs) and demonstrate that blinking can be suppressed by allowing photoinduced charge to quickly exchange with a metallic reservoir. Further, we show that ZnO NPs coated on a m…

We analyze the optical spectra of photonic structures composed of hBN films with embedded WS2 excitonic monolayers, designed to maximize light–matter interaction and Rabi splittings. These structures are enclosed within SiO2 layers and probed in an attenuated total reflection configuration using Si prisms. The optical spectra show resonances due to strong exciton–guided mode interactions and the …

Negative carbon (C−) and oxygen (O−) ions are expected to find wide applications for ion implantation processes. However, systematic experimental data required for their efficient generation and the elucidation of their underlying atomic processes are lacking. In this study, we systematically measured the angular and incident beam energy dependencies of the reflected carbon and oxygen ion propert…

GaFeO3-type oxide films are promising multiferroic materials due to their coexistence of ferroelectricity and ferrimagnetism at room temperature. For device applications, understanding the thickness dependence of their ferroelectric properties is crucial. In this study, we investigated the ferroelectric behavior of GaFeO3-type oxide films as a function of thickness. Notably, the GaFeO3-type struc…

The mathematical expressions for the effective carrier masses of zinc blende semiconductors are derived, with particular emphasis on their dependence on carrier energy. In this work, Hamiltonian matrix diagonalization is employed to obtain the band energies, followed by the Kane approximation to derive analytical expressions for energy-dependent effective masses. Unlike conventional approaches th…

We present our progress of a compact laser-plasma extreme ultraviolet (EUV) source based on Xe/He double-stream gas jets irradiated by a 700-mJ Nd:YAG laser. The source was characterized using a flat-field spectrometer, an absolutely calibrated EUV energy meter, and a pinhole camera imaging system. A Maximum single-pulse EUV intensity of 2.36 mJ was achieved at 13.5 nm (2% bandwidth, 2π sr), corr…

Hall effect and conductivity measurements over a wide temperature range of 20–300 K are carried out on gallium-doped silicon subjected to 3.5 MeV electron and 15 MeV proton irradiation at room temperature. Electrical data obtained provide convincing evidence that impurity atoms are involved in interactions with intrinsic point defects during irradiation. As a result, heavy losses of the shallow a…

Radioisotope (60Co) and particle accelerator (10 s MeV proton) sources are both commonly used to assess the effects of the space radiation environment on electronics and detectors; however, the efficiency of 60Co gammas to generate displacement damage is poorly understood. Here, 60Co and 54.3 MeV proton degradation of the minority carrier lifetime are compared for an InAs/InAsSb superlattice and …

An analytical compact model is developed for the mobile charge density of multiple-channel field-effect transistors based on the III-nitride material system. Two-dimensional electron and hole gases can be potentially induced by spontaneous and piezoelectric polarization in polar heterostructures. Focusing on the active region of devices that employ a multiple quantum-well layout, the total electr…

The Goos–Hänchen-like (GH) shift of electron wavepackets at potential interfaces provides a powerful method for probing the properties of quantum materials. In this work, we theoretically investigate the spin- and valley-resolved GH shift in a monolayer of jacutingaite (Pt2HgSe3), a quantum spin Hall insulator, subjected to both a perpendicular electric field and off-resonant circularly polarized…

Using density functional theory combined with thermochemical data, we analyze the formation of native and carbon-related defects in yttrium aluminum garnet (YAG) grown in a CO-containing atmosphere. The concentrations of various defect species in as-grown YAG are computed as functions of the partial pressures of CO, CO2, and O2. Under reducing conditions, carbon preferentially forms negatively ch…

LaCoO3 (LCO) undergoes a cubic to rhombohedral structural phase transition at ∼1600 K, a metal–insulator transition at ∼550 K, and a spin-state transition at ∼100 K. The thermodynamics of spin-state phase transitions for LCO have been studied using the 2-4-6 Landau–Ginzburg (LG) free energy functional (ΔG) developed in terms of mode amplitude of octahedral tilt (primary order parameter), symmetry…

Generalized ellipsometry can uncover the optical properties of anisotropic materials, in which the light–matter interaction alters the polarization state. In the terahertz frequency range, generalized ellipsometry has been infrequently realized due to the challenge of rapidly controlling and measuring THz polarization. Here, we report the development and calibration of a high-efficiency terahertz…

This study discusses a structural relaxation model for stressed thermal oxide films grown on Si (100) substrates at a temperature that is too low for viscous flow to relax an Si thermal oxide film. This relaxation model had been developed on the basis of activation energy analysis through ab initio calculations on transformations between different crystal types. The analysis revealed a systematic…

The electronic energy loss spectra of ceria (CeO2) irradiated with swift heavy ions (27 MeV Xe and 946 MeV Au) in the electronic slowing down regime were measured for bulk sintered samples and nanoparticles by using a double Cs-corrected transmission electron microscope. The low-loss region as well as the core-loss region, including the oxygen K-edge and cerium M4, 5 white lines, were recorded. N…

The strength of diamond is critical for both static and dynamic high-pressure research. Under the compression of shock waves in the range of hundreds of gigapascals, single-crystal diamond exhibits strong time-dependent inelastic deformation, making it a crucial issue for the development of an accurate material description of diamond capsules used in inertial confinement fusion (ICF). Here, we pr…

Thermoelectric (TE) performance of complex nanostructured materials is strongly influenced by the morphology and transport properties of the grain boundaries, or interfacial regions connecting together individual grains. However, experimental and theoretical efforts probing such characteristics have been very limited so far. Here, we utilized the finite element method based calculations to evalua…

We report a comprehensive study of two-dimensional (2D) valentinite antimony oxide (β-Sb2O3) exfoliated from its natural bulk form. The flakes exhibit well-defined morphology, low surface roughness, and preserved orthorhombic structure. Raman and infrared nano-spectroscopy reveal distinct vibrational modes, confirming the crystallinity and vibrational anisotropy of the material. Conductive atomic…

We demonstrate that facet-controlled epitaxial lateral overgrowth enables the formation of regular, strain-relieving misfit dislocation (MD) arrays at {11−22} interfaces and results in relaxed growth of AlGaN on native GaN substrates (threading dislocation density <104 cm−2). Complementary plan-view and cross-sectional transmission electron microscopy studies confirmed the presence of unif…