We demonstrate a classical analogue of electromagnetically induced transparency (EIT) in highly flexible planar terahertz metamaterial (MM) comprised three-gap split ring resonators. The keys to achieve EIT this system are the frequency detuning and hybridization processes between two bright modes coexisting same unit cell as opposed bright-dark modes. present experimental verification two-bright mode coupling for EIT-MM context numerical results theoretical analysis based on coupled Lorentz...

First-generation n-i-GeSn/p-Si(100) photodiode detectors with Ge0.98Sn0.02 active layers were fabricated under complementary metal oxide semiconductor compatible conditions. It is found that, even at this low Sn concentration, the detector quantum efficiencies are higher than those in comparable pure-Ge device designs processed temperature. Most significantly, spectral range of GeSn responsivity dramatically increased—to least 1750 nm—well beyond direct band gap Ge (1550 nm). This allows...

Direct-gap photoluminescence has been observed at room temperature in Ge1−ySny alloys grown on (001) Si substrates. The emission wavelength is tunable over a 90 meV (200 nm) range by increasing the Sn concentration from y=0 to y=0.03. A weaker feature lower energy assigned indirect gap transitions, and separation between direct peaks found decrease as function of y, expected for these alloys. These results suggest that represent an attractive alternative Ge fabrication laser devices Si.

The compositional dependence of the lowest direct and indirect band gaps in Ge1−ySny alloys has been determined from room-temperature photoluminescence measurements. This technique is particularly attractive for a comparison two transitions because distinct features spectra can be associated with gaps. However, detailed modeling these room temperature required to extract gap values high accuracy determine Sn concentration yc at which alloy becomes semiconductor. For gap, this accomplished...

The optical properties of Ge1−ySny alloys (y ∼ 0.02) grown by chemical vapor deposition on Si substrates have been studied using spectroscopic ellipsometry and photocurrent spectroscopy. system shows a 10-fold increase in absorption, relative to pure Ge, at wavelengths corresponding the C-telecommunication band (1550 nm) 20-fold L-band (1620 nm). Measurements series samples with different thicknesses reveal nearly identical dielectric functions, from which composition reproducibility growth...

Electroluminescence spectra from Si/Ge1−ySny heterostructure diodes are reported. The observed emission is dominated by direct gap optical transitions and displays the expected compositional dependence of peak energy. Weaker indirect also observed, their energies consistent with a closing indirect-direct separation as Sn concentration increased. intensity EL shows superlinear on injection current, which modeled using Van Roosbroeck–Shockley expression for intensity. model assumes...

Ge/Si heterostructure diodes based on n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">++</sup> Si(100)/i-Ge/p-Ge and p Si(100)/i-Ge/n-Ge stacks intrinsic region thickness of ~350 ~900 nm, respectively, were fabricated using a specially developed synthesis protocol that allows unprecedented control film microstructure, morphology, purity at complementary metal-oxide-semiconductor compatible conditions. From growth doping perspective, main...

The optical emission spectra from Ge films on Si are markedly different their bulk counterparts. Whereas is dominated by the material's indirect gap, photoluminescence signal mainly associated with its direct band gap. Using a new class of Ge-on-Si grown recently introduced CVD approach, we study and intrinsic doped samples conclude that origin discrepancy lack self-absorption in thin combined deviation quasi-equilibrium conditions conduction band. latter confirmed simple model suggesting...

We investigate the possibility of creating an intermediate band semiconductor by supersaturating Si with a range transition metals (Au, Co, Cr, Cu, Fe, Pd, Pt, W, and Zn) using ion implantation followed pulsed laser melting (PLM). Structural characterization shows evidence either surface segregation or cellular breakdown in all investigated, preventing formation high supersaturations. However, concentration-depth profiling reveals that regions supersaturated Au Zn are formed below breakdown....

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation J. Lander, H. Schreiber, T. M. Buck, R. Mathews; MICROSCOPY OF INTERNAL CRYSTAL IMPERFECTIONS IN Si p‐n JUNCTION DIODES BY USE ELECTRON BEAMS. Appl. Phys. Lett. 1 December 1963; 3 (11): 206–207. https://doi.org/10.1063/1.1753850 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley...

Previously developed methods used to grow Ge1−ySny alloys on Si are extended Sn concentrations in the 1019−1020 cm−3 range. These shown be sufficient engineer large increases responsivity of detectors operating at 1550 nm. The dopant levels incorporated temperatures 370–390 °C range, yielding atomically smooth layers devoid threading defects high growth rates 15–30 nm/min. conditions far more compatible with complementary metal-oxide semiconductor processing than and required achieve same...

We report the polarization-dependent electromagnetic response from a series of novel terahertz (THz) metasurfaces where asymmetry is introduced through displacement two adjacent metallic arms separated by distance δ.For all polarization states, symmetric metasurface exhibits low quality (Q) factor fundamental dipole mode.By breaking symmetry, we experimentally observe secondary dipole-like mode with Q nearly 9× higher than resonance.As δ increases, f 1 redshifts and 2 blueshifts creating...

Abstract We demonstrate a single-layer THz metadevice that exhibits cross polarization transmission, key factor to achieve optical activity. The device is comprised of two-dimensional array split ring resonators, each with vanadium oxide (VO 2 ) pad, integrated into one the two capacitive gaps unit cell. Through numerical investigations we find as conductivity VO increases amplitude cross-polarization intensity decreases but maintains wider broadband range than previously reported for single...

We report an investigation on the photo-response from a GeSn-based photodetector using tunable laser with range of incident light power. An exponential increase in photocurrent and decay responsivity optical power intensity were observed at higher range. Time-resolved measurement provided evidence that indicated monomolecular bimolecular recombination mechanisms for photo-generated carriers different intensities. This establishes appropriate operation.

Prototype detector structures were fabricated on Si substrates using Ge1−ySny as active material for the first time. This alloy system covers entire near-IR telecommunication spectrum and grows at a low temperature of 350°C, compatible with complementary metal-oxide-semiconductor (CMOS) technology. Processing protocols developed photolithography-based patterning subsequent etching, CMOS metallization, formation low-resistivity Ohmic contacts. A generation devices based as-grown layers was...

The use of ion implantation damage to getter deleterious impurities from diode space-charge regions is studied. Ion into the neutral near p-n junctions shown cause substantial reduction in incidence type white video defects (excessive-leakage current diodes) caused by impurity precipitation and often found a cyclonic pattern. It that using doses 1016 cm−2 phosphorus (50 keV), ≥1015 arsenic (150 ≥3×1015 argon keV) can completely eliminate these defects. In addition, dark currents targets...

Photoluminescence has been observed at room temperature in phosphorus-dopedGe1−ySny/Si(100) alloys containing carrier densities the 1-6 × 1019 cm−3 range. The emission intensity is one order of magnitude stronger than similar undoped films, and enhancement consistent with theoretical predictions for doped-Ge like materials. ratio Idir/Iind direct over indirect gap found to increase high-Sn concentrations as a result reduced Γ-L valley separation Ge1−ySny alloys. These results confirm that...

Fabrication of p-Si(111) layers with Ti levels well above the solid solubility limit was achieved via ion implantation 15 keV 48Ti+ at doses 1012 to 1016 cm−2 followed by pulsed laser melting using a Nd:YAG (FWHM = 6 ns) operating 355 nm. All implanted were examined cross-sectional transmission electron microscopy, and only implant dose showed evidence clustering in microstructure pattern Ti-rich zones. The liquid phase diffusivity diffusive velocity Si estimated be 9 × 10−4 cm2/s (2 ± 0.5)...

We report new approaches based on rational design and preparation of chemical vapor deposition precursors involving novel main-group hydrides to fabricate families Si-based semiconductors prototype devices that display compositional structural inheritance, from the parent molecule solid end product. This methodology enables materials synthesis at extraordinarily low temperatures are compatible with complementary metal-oxide-semiconductor (CMOS) processing/selective growth provides means for...

We employ the process of non-degenerate four-wave mixing Bragg scattering (FWM-BS) to demonstrate all-optical control in a silicon platform. In our configuration, strong, non-information-carrying pump is mixed with weak and an input signal silicon-on-insulator waveguide. Through optical nonlinearity this highly-confining waveguide, controls wavelength conversion from idler, leading controlled depletion signal. The strong pump, on other hand, plays role constant bias. work, we show...

Traditional lattice-induced transparency demonstrations are activated by varying the meta-atom lattice constant such that plasmonic and modes interfere. Here we report on observation of enhanced coupling between two eigenmodes (first- second-order) parameter in a symmetric split ring resonator design. The higher-order quasi-dark mode blueshifts, introducing strong with fundamental bright for periods above 345 μm. Numerical simulations verified experimentally supplemented two-oscillator model...