Layered black phosphorus has been attracting great attention due to its interesting material properties which lead a plethora of proposed applications. Several approaches are demonstrated here for covalent chemical modifications layered in order form P-C and P-O-C bonds. Nucleophilic reagents highly effective modification phosphorus. Further derivatization investigated were based on radical reactions. These not as nucleophilic the surface The influence electronic structure was using ab...

We investigated the magnetotransport of InAs nanowires grown by selective-area metal-organic vapor phase epitaxy. In temperature range between 0.5 and 30 K reproducible fluctuations in conductance upon variation magnetic field or backgate voltage are observed, which attributed to electron interference effects small disordered conductors. From correlation magnetoconductance phase-coherence length ${l}_{\ensuremath{\phi}}$ is determined. At lowest temperatures found be at least 300 nm while...

The role of Si during the metal–organic vapor phase epitaxy GaN rods is investigated. Already a small amount strongly enhances vertical growth GaN. Reactive ion etching experiments show that inner volume rod much more etched than m-plane surface layer. Transmission electron microscopy and energy dispersive X-ray spectroscopy measurements reveal predominiantly incorporated in layer sidewall facets rods. formation SiN prevents on m-planes mobility atoms promoting growth. Annealing demonstrate...

In the present paper, studies on state of strain in single and ensembles nanocolumns investigated by photoluminescence spectroscopy will be presented. The GaN were either grown a bottom-up approach or prepared top-down etching compact layers Si(111) sapphire (0001) substrates. Experimental evidence for relaxation was found. difference development value different could verified spatially resolved micro-photoluminescence separated from their substrate. A common D0X spectral position at 3.473...

The effect of Si-doping on the morphology, structure, and transport properties nanowires was investigated. were deposited by selective-area metal organic vapor phase epitaxy in an N2 ambient. It is observed that doping systematically affects nanowire morphology but not structure nanowires. However, wires are greatly affected. Room-temperature four-terminal measurements show with increasing dopant supply conductivity monotonously increases. For highest level higher a factor 25 compared to...

In this Perspective, we will introduce possible future developments on group III-nitride nano-LEDs, which are based current achievements in rapidly arising research-technological field. First, the challenges facing their fabrication and characteristics be reported. These set a broader context with primary applications lighting, display technology, biology, sensing. following, center advanced microscopy, lithography, communication, optical computing. We discuss unconventional device prospects...

The magnetoconductivity of ${\mathrm{Ga}}_{x}{\mathrm{In}}_{1\ensuremath{-}x}\mathrm{As}∕\mathrm{InP}$ quantum wires with widths in the range $1220--250\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ was investigated. finite zero-field spin splitting our samples gives rise to relaxation and weak antilocalization wide wires. In contrast, for narrow wires, only weak-localization behavior is seen even though independent wire width. observed renormalization spin-relaxation length due purely geometrical...

We investigated the transport properties of GaAs/InAs core/shell nanowires grown by molecular beam epitaxy. Owing to band alignment between GaAs and InAs, electrons are accumulated in InAs shell as long thickness exceeds 12 nm. By performing simulations using a Schrödinger–Poisson solver, it is confirmed that confined states present shell, which depleted if below threshold value. The existence tubular-shaped conductor proved magnetoconductance measurements at low temperatures. Here, flux...

We report on an alternative illumination concept for a future lithography based single-photon emitters and important technological steps towards its implementation. Nano light-emitting diodes (LEDs) are chosen as the photon emitters. First, development of their fabrication integration technology is presented, then optical characteristics assessed. Last, size-controlled nano-LEDs, well positioned in array, electrically driven utilized illumination. Nanostructures lithographically formed,...

We report on the technology and growth optimization of GaAs/InAs core/shell nanowires. The GaAs nanowire cores were grown selectively by metal organic vapor phase epitaxy (SA-MOVPE) SiO(2) masked (111)B templates. These structured a complete thermal nanoimprint lithography process, which is presented in detail. influence subsequent InAs shell temperature morphology crystal structure was investigated scanning transmission electron microscopy order to obtain desired homogeneous uniform...

We generate terahertz (THz) transients by illuminating a few-nanometer-thick Ta/NiFe/Pt nanolayers with train of linearly polarized 100-fs-wide laser pulses. The are ∼1-ps-wide free-space propagating bursts electromagnetic radiations amplitudes that magnetically and optically tunable. Their spectral frequency content extends up to 5 THz, the 3-dB cutoff is at 0.85 THz. observed transient signals originate from NiFe/Pt bilayer, their amplitude dependence on external magnetic field, applied in...

We propose a device concept for hybrid nanocrystal/III-nitride based nano-LED. Our approach is on the direct electro-optical pumping of nanocrystals (secondary excitation) by electrically driven InGaN/GaN nano-LEDs as primary excitation source. To this end, universal optoelectronic platform was developed large range optically active nano- and mesoscopic structures. The advantage that emission can be induced without need contacting them. proof principal demonstrated CdSe nanocrystals. with...

Weak antilocalization and the Shubnikov--de Haas effect were investigated in ${\mathrm{Al}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{N}∕\mathrm{Ga}\mathrm{N}$ two-dimensional electron gases. The weak measurements on a gated sample revealed constant spin-orbit scattering length, which does not change if Al content or thickness of ${\mathrm{Al}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{N}$ barrier layer is varied. occurrence coupling assigned to lack crystal inversion symmetry. Although...

We report on the fabrication and measurements of planar mesoscopic Josephson junctions formed by InAs nanowires coupled to superconducting Nb terminals. The use Si-doped InAs-nanowires with different bulk carrier concentrations allowed tune properties junctions. have studied junction characteristics as a function temperature, gate voltage, magnetic field. For high doping in nanowire, supercurrent values up 100 nA are found. Owing superconductor, coupling persists at temperatures 4 K. In all...

Abstract Layered black phosphorus has been attracting great attention due to its interesting material properties which lead a plethora of proposed applications. Several approaches are demonstrated here for covalent chemical modifications layered in order form P−C and P‐O‐C bonds. Nucleophilic reagents highly effective modification phosphorus. Further derivatization investigated were based on radical reactions. These not as nucleophilic the surface The influence electronic structure was using...

Spin-orbit scattering in a polarization-doped Al0.30Ga0.70N∕GaN two-dimensional electron gas with one occupied subband is studied at low temperatures. At magnetic fields weak antilocalization observed, which proves that spin-orbit occurs the gas. From measurements various temperatures elastic time τtr, dephasing τϕ, and τso are extracted. Measurements tilted were performed, order to separate spin orbital effects.

Abstract Metalorganic vapor phase epitaxy (MOVPE) of GaN was performed using hydrogen (H 2 ), nitrogen (N ) and H /N mixtures thereof as the carrier gas in high temperature buffer growth range. The effect on structural morphological characteristics epilayers systematically studied interference atomic force microscopy (AFM), photoluminescence (PL) measurements at K, Raman spectroscopy X‐ray diffraction (XRD). higher N content gas, more pinholes are observed, lower compressive strain...

The effect of a small dose gamma irradiation on transport characteristics the two-dimensional electron gas (2DEG) in AlGaN∕GaN heterostructures was investigated. It is shown that carrier concentration remains practically unchanged after an 106rad, while 2DEG mobility exhibits considerable increase. results are explained within model takes into account relaxation elastic strains and structural-impurity ordering occurring barrier layer under irradiation.

We report the results of direct measurements and a theoretical investigation in-plane effective mass in two-dimensional electron gas nominally undoped AlGaN/GaN heterostructures with different degree quantum confinement. It is shown that most cases conduction band nonparabolicity effect overestimated wave-function penetration into barrier layer should be taken account. The contribution hybridization determined to play dominant role. edge value deduced (0.2±0.01)m0.

We report on the conditions necessary for electrical injection of spin-polarized electrons into indium nitride nanowires synthesized from bottom up by molecular beam epitaxy. The presented results mark first unequivocal evidence spin III-V semiconductor nanowires. Utilizing a newly developed preparation scheme, we are able to surmount shadowing effects during metal deposition. Thus, avoid strong local anisotropies that arise if ferromagnetic leads wrapping around nanowire. Using combination...