The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we present electrically pumped GaAsBi quantum well (QW) laser diodes (LDs) grown by molecular beam epitaxy. The LDs reveal a record long lasing wavelength of 1.14 µm at 300 K and can be operated under CW excitation up to 273 K. They also show high performance with an internal quantum efficiency of 86% and an internal optical loss of 10 cm−1. The characteristic temperature is 79 K in...
A dual-nanowire heterostructure with a GeSn layer laterally laying on Ge nanowires is demonstrated by MBE. The strain field analyzed by FEM shows that the novel proposal can significantly release the compressive strain in GeSn for potential direct bandgap conversion as a Si-based light source.
The hyperspectral image has the advantages of wide spectral range and the high spectral resolution, and is widely applied in the terrain classification. In this paper, we study the airborne hyperspectral image classification methods using the airborne hyperspectral image. Considering the hyperspectral image has amounts of bands and there is redundancy among the bands, the principle component analysis...
The earthquake disaster loss assessment is of great significance for the disaster recovery and reconstruction, the resettlement and the economic sustainable development. The Remote Sensing (RS) technique can help rapidly obtain the earthquake damage information. The paper proposes a methodology and procedure of building loss assessment based on the remote sensing and km grid-based building data, and...
It has been theoretically predicted that 1.9% biaxial tensile strain can convert Ge [1], which is compatible with Si CMOS technology, into a direct band-gap semiconductor, making it a candidate material for light sources on Si [2, 3]. Combining the advantage of tensile strain with quantum dot (QD), we proposed that tensile-strained QD is a new route toward light emission from Ge [4]. In this work,...
In this paper, I present recent progresses on epitaxial growth and material characterizations of novel dilute III-PBi and III-SbBi. High quality dilute bismide thin films can be epitaxially grown by molecular beam epitaxy in a narrow growth parameter window. Up to 13% and 4.3% Bi is incorporated in GaSbBi and InPBi, respectively, and majority Bi atoms are at the lattice position as confirmed by Rutherford...
It is theoretically predicted that biaxial tensile strain as much as 1.4% can make up the 136 meV gap between the Γ and L valley in Ge [1], thereby converting Ge from an indirect-bandgap semiconductor into a direct-bandgap one that can emit light efficiently covering the telecom band. The mobility of both carriers is dramatically increased simultaneously. Therefore, tensile-strained Ge has drawn large...
GaSb1−xBix thin films with 0 ≤ x ≤ 13% were grown by molecular beam epitaxy. The Bi content, lattice expansion and crystal structure were investigated by Rutherford backscattering spectroscopy, X-ray diffraction and transmission electron microscopy. Photoluminescence spectra of the GaSb1−xBix alloys with various Bi contents were studied at 77 K. The bandgap energy of GaSb1−xBix is decreased effectively...
Folded dipole is proposed to mitigate the incompatibility between magnetic resonance imaging and transcranial magnetic stimulation. A numerical study by applying the method of moment demonstrate that the effects of eddy current induced on a stimulator can be mitigated by quadrature phase combination of signals from adjacent folded dipoles.
InAs/GaAs quantum dot (QD) laser structures were fabricated using gas source molecular beam epitaxy (GSMBE) on Ge (100) substrate. Low temperature grown GaAs buffer layer prevented formation of anti-phase domain (APD). Growth temperature and deposition thickness of InAs were optimized, respectively. Active region consists of five stacked InAs QD layers separated by 40 nm GaAs space layer. Ridge waveguide...
InPBi crystalline thin films with a bismuth concentration up to 4.8% have been successfully grown using molecular beam epitaxy for the first time. This novel material reveals strong and broad photoluminescence in the wavelength range of 1–2.5 μm at room temperature, although the absorption measurements point out a near band-gap absorption character. Various structural and optical characterization...
When the speed of the train is 350km/h, it only takes about 7ms for the on-board antenna of BTM to pass the effective range of a balise. On-board antenna needs to accomplish a communication with balise within such a little time that it is essential for on-board antenna to have a good performance of transmitting and receiving signal. Therefore, it is significant to study the optimization of the performance...
Dilute bismides are a group of emerging materials with unique properties. Incorporation of a small amount of Bi in common III–V host materials results in large band-gap reduction and strong spin-orbit splitting, leading to potential applications in near-infrared (NIR) and mid-infrared (MIR) optoelectronics. Recent progresses on molecular beam epitaxy (MBE) of novel III-Sb-Bi, i.e. GaSbBi and InSbBi...
Magnetic Resonance Imaging (MRI) results in overall quality that usually calls for human intervention in order to correctly identify details present in the image. More recently, interest has arisen in automated processes that can adequately segment medical image structures into substructures with finer detail than other efforts to-date. Relatively few image processing methods exist that are considered...
Since the airship-borne camera recorder is easily effected by the complex weather conditions such as fog and haze etc, we adopt the multiple scales Retinex algorithm with color restoration to remove fog. It retains the details of the image enhanced and restores the genuine color of the image. And then the algorithm based on SIFT feature extraction and match in the Euclidean space is utilized to estimate...
In this work, the ability of subharmonic aided pressure estimation (SHAPE) to noninvasively estimate cardiac right ventricular pressures was investigated. Five canines received Sonazoid (GE Healthcare, Oslo, Norway) infusion (0.015 µl/kg/min) and were scanned using a Sonix RP ultrasound scanner (Ultrasonix Medical Corp, Richmond, BC, Canada) with a PA4-2 phased array (transmit/receive: 2.5/1.25 MHz)...
III–V-Bi compounds have received considerable attention recently due to a number of interesting material properties. For example, adding a small amount of Bi atoms in conventional III–Vs leads to a large bandgap reduction that occurs predominately in the valence band, about 88 meV/%Bi in GaAsBi. The Bi incorporation affects only the valence band structures and has little influence on electrons. Compared...
We proposed a QBC algorithm for fast direct solution of the PMCHWT formulation for dielectric bodies. This algorithm explores the checkerboard symmetry of the impedance matrix and halves both memory and CPU time as compared to regular block LU decomposition. In the examples we have tested, the resultant CPU time scales around O(N2) and memory scales around O(N3/2).
Wetland ecosystems have complex habitat characteristics due to the wetland existing between lands and water bodies, however, satellite remote sensing images have normally mixed pixels because of their spectral characteristics of the riverine surface feature, and it is very difficult to extract the specific information of aquatic ecosystems. Hence satellite remote sensing images are hardly to match...
A uniformity, high efficiency and large volume microwave plasma source has been developed, which consists of a 1-10 kW 2.45 GHz magnetron power supply, microwave transmission and monitoring system, microwave power splitter, adjustable short-circuit plunger and two parallel rectangular waveguides with axial slots regularly positioned on its inner side. The design parameters and electric field existing...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.