The results of magnetoconductivity measurements in ${\mathrm{Ga}}_{\mathit{x}}$${\mathrm{In}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$As quantum wells are presented. observed appears due to the interference, which lead weak localization effect. It is established that details controlled by spin splitting electron spectra. A theory developed takes into account both linear and cubic wave-vector terms splitting, arise lack inversion center crystal, as well appear when itself asymmetric. that,...

A dramatic increase of the conduction band electron mass in a nitrogen-containing III–V alloy is reported. The found to be strongly dependent on nitrogen content and concentration with value as large 0.4m0 In0.08Ga0.92As0.967N0.033 6×1019 cm−3 free electrons. This more than five times larger effective GaAs comparable typical heavy hole masses compounds. results provide critical test fully confirm predictions recently proposed anticrossing model electronic structure III–N–V alloys.

We report on room temperature terahertz generation by a submicron size AlGaN/GaN-based high electron mobility transistors. The emission peak is found to be tunable the gate voltage between 0.75 and 2.1 THz. Radiation frequencies correspond lowest fundamental plasma mode in gated region of transistor channel. Emission appears at certain drain bias thresholdlike manner. Observed interpreted as result Dyakonov–Shur wave instability two-dimensional gas.

Dislocation-free high-quality AlGaN/GaN heterostructures have been grown by molecular-beam epitaxy on semi-insulating bulk GaN substrates. Hall measurements performed in the 300 K–50 mK range show a low-temperature electron mobility exceeding 60 000 cm2/V s for an sheet density of 2.4×1012 cm−2. Magnetotransport experiments up to 15 T exhibit well-defined quantum Hall-effect features. The structures corresponding cyclotron and spin splitting were clearly resolved. From analysis Shubnikov de...

Double-barrier GaN resonant tunneling diodes with AlGaN barriers were fabricated on bulk (0001) single-crystal substrates. Layers grown using molecular-beam epitaxy a rf plasma nitrogen source. Single of 6μm diameter prepared by inductively coupled reactive ion etching. For many clear negative differential resistance is observed around 2V peak currents 10kA∕cm2 and peak-to-valley ratio about 2 at room temperature. Its observation does not depend specific conditions measurement; however, it...

The progress in the growth of nitride-based laser diodes (LDs) made by plasma-assisted molecular beam epitaxy (PAMBE) is reviewed. In this work we describe GaN and InGaN peculiarities, p-type doping efficiency, properties quantum wells (QWs) grown PAMBE. We demonstrate continuous wave (cw) LDs operating range from 410 to 482 nm. These were on low dislocation (0 0 1) c-plane bulk substrate, which allow one fabricate cw with a lifetime exceeding 2000 h. Also, ultraviolet at 388 nm (2 −2...

In this paper, we carry out a comprehensive review of the nitrogen-induced modifications electronic structure Ga1−yInyNxAs1−x alloys. We study in detail behaviour conduction-band effective mass as function Fermi energy, nitrogen content and pressure. From measurements plasma frequency for samples with different electron concentrations have determined dispersion relation lowest conduction band. also studied composition, temperature pressure dependent optical absorption spectra on...

We report on high magnetic fields (up to 40 T) cyclotron resonance, quantum Hall effect and Shubnikov-de-Hass measurements in frequency transistors based Si-doped GaN–AlGaN heterojunctions. A simple way of precise modelling the absorption these heterojunctions is presented. clearly establish two-dimensional electrons be dominant conducting carriers determine precisely their in-plane effective mass 0.230±0.005 free electron mass. The increase with an carrier density observed explained by...

Blue and violet light-emitting devices based on III-nitrides caused an ongoing revolution in general lighting. One of the highly deliberated discussions this field is devoted to problem called "green gap", which a lack efficient emitters spectral regime. reasons behind insufficient internal quantum efficiency (IQE) green III-nitride related confined Stark effect. In paper we present counterintuitive feature well systems with large built-in electric that leads huge enhancement IQE. We show,...

We demonstrate true-blue 450 nm tunnel junction (TJ) laser diodes (LDs) grown by plasma-assisted molecular beam epitaxy (PAMBE). The absence of hydrogen during PAMBE growth allows us to achieve TJs with low resistance. compare TJ LDs standard construction p-type metal contact. For both types LD, the threshold current density is around 3 kA/cm2 and slope efficiency 0.5 W/A. do not observe any significant changes in optical losses differential gain compared LDs. resistivity for densities...

Ultrasmall micro-light-emitting diodes (μLEDs), sized below 10 μm, are indispensable to create the next-generation augmented and virtual reality (AR/VR) devices. Their high brightness low power consumption could not only enhance user experience by providing vivid lifelike visuals but also extend device longevity. However, a notable challenge emerges: decrease in efficiency with reduced size. This study casts light on this critical issue investigating lateral carrier diffusion ion-implanted...

Abstract Recent research focused on single photon emitters (SPEs) hosted by layered semiconductors, particularly hexagonal boron nitride (hBN), has revealed a promising alternative to quantum dots (QDs) for generating single, indistinguishable photons. hBN‐based SPEs offer lower material costs, room temperature emission, and easy integration into potential optoelectronic devices due the structure of host crystal. This work presents compact hybrid electroluminescence devices, in which GaN...

Despite the ubiquity of semiconductor-based emitters in optoelectronic devices we use every day, obstacles still remain to unlock their full potential. One these lies long-wavelength GaN-based laser diodes (LDs). It is common knowledge that InGaN quantum wells (QWs) exhibit extremely large built-in polarization, which helps obtain emission light-emitting diodes, thanks quantum-confined Stark effect. However, this paper, it shown order achieve LDs, wide QWs might be preferential. The lasing...

Phosphor-coated III-nitride light-emitting diodes (III-N LEDs) are currently the most efficient sources of white light. However, standard LEDs require a direct current (DC) supply, while power in electrical grid is distributed as alternating (AC). Considerable efforts therefore devoted to development directly AC-powered semiconductor light sources. In this paper, we demonstrate bidirectional emitting diode (BD LED) that emits under positive and negative bias from same active region [1]. The...

We have measured the interband optical absorption of a free-standing sample Ga0.96In0.04As0.99N0.01 in wide energy range from 1 to 2.5 eV. found that fundamental edge is shifted by 150 meV towards lower energies, and coefficient at higher energies exhibits substantial reduction comparing GaAs. By removing GaAs substrate, we were able get an experimental insight into transitions density state this material. The changes can be understood within band anticrossing model predicting conduction...

We report on the InGaN multiquantum laser diodes (LDs) made by rf plasma-assisted molecular beam epitaxy (PAMBE). The operation at 408nm is demonstrated room temperature with pulsed current injections using 50ns pulses 0.25% duty cycle. threshold density and voltage for LDs cleaved uncoated mirrors are 12kA∕cm2 (900mA) 9V, respectively. High output power of 0.83W obtained during pulse 3.6A 9.6V bias slope efficiency 0.35W∕A. structures deposited high-pressure-grown low dislocation bulk GaN...

We have carried out comprehensive studies of the nitrogen-induced modifications electronic structure ${\mathrm{In}}_{y}{\mathrm{Ga}}_{1\ensuremath{-}y}{\mathrm{As}}_{1\ensuremath{-}x}{\mathrm{N}}_{x}$ alloys. Temperature- and composition-dependent optical absorption spectra been measured on free-standing layers thin films lattice matched to GaAs with $0<~x=3y<~0.025$ in photon energy range 0.8--2.5 eV. The measurements provided information transitions at \ensuremath{\Gamma} point Brillouin...

The results on growth and magnetotransport characterization of AlGaN∕GaN heterostructures obtained by plasma assisted molecular beam epitaxy dislocation-free (below 100cm−2) GaN high pressure synthesized bulk substrates are presented. record mobilities the two dimensional electron gas (2DEG) exceeding 100000cm2∕Vs at liquid helium temperature 2500cm2∕Vs room reported. An analysis field conductivity tensor components allowed us to discuss main scattering mechanisms confirm unambiguously 2DEG...

We report on optically pumped lasing at 500 nm InGaN laser structures grown by plasma assisted molecular beam epitaxy. The were under group III-rich conditions bulk (0001) GaN substrates. influence of the nitrogen flux and growth temperature indium content layers was studied. demonstrate that elevated temperatures, where appreciable dissociation rate for In-N bonds is observed, increases with increasing flux. show higher temperatures improves optical quality quantum wells, which crucial...

The influence of InxGa1−xN waveguide on the properties blue (λ = 450 nm) laser diodes grown by plasma-assisted molecular beam epitaxy was studied. threshold current density reduced 50% (to 3.6 kA/cm2) when indium content increased from x 0.04 to 0.08. This is explained a substantial enhancement optical confinement factor for high-In-content waveguide, which increases differential modal gain. Furthermore, we observed decrease in losses Mg-doped layers were separated active region thicker...

Abstract A novel design consisting of a thick InGaN waveguide is proposed to fully eliminate leakage the GaN substrate in nitride laser diodes. The based on effective refractive index engineering and does not require commonly used AlGaN claddings. conditions required optical are discussed. Experimental results from eight blue diodes with different indium contents thicknesses grown by plasma-assisted molecular beam epitaxy presented validate theoretical results.

We demonstrate a stack of two III-nitride laser diodes (LDs) interconnected by tunnel junction grown plasma-assisted molecular beam epitaxy. Hydrogen-free growth is used to obtain as-grown p-type conductivity essential for buried junctions (TJ). show the impact design junction. In particular, we that, apart from beneficial piezoelectric polarization inside TJ, heavy doping reduces differential resistivity even further. The device starts lase at wavelength 459 nm with slope efficiency (SE)...