A5030864027- Photonic and Optical Devices
- Semiconductor Lasers and Optical Devices
- Receptor Mechanisms and Signaling
- Gyrotron and Vacuum Electronics Research
- Antenna Design and Optimization
- Semiconductor Quantum Structures and Devices
- Superconducting and THz Device Technology
- Computational Drug Discovery Methods
- Microwave Engineering and Waveguides
- Antenna Design and Analysis
- Laser Design and Applications
- Neuropeptides and Animal Physiology
- Physics of Superconductivity and Magnetism
- Wireless Communication Networks Research
- Chemical Synthesis and Analysis
- Radio Wave Propagation Studies
- Mechanical and Optical Resonators
- Supramolecular Self-Assembly in Materials
- Pancreatic function and diabetes
- Melanoma and MAPK Pathways
- Photochromic and Fluorescence Chemistry
- Electromagnetic Compatibility and Measurements
- CAR-T cell therapy research
- Power Line Communications and Noise
- Advanced MIMO Systems Optimization
University of Copenhagen
2017-2024
Technical University of Denmark
1972-2023
University of the Faroe Islands
2002
It will be shown that spontaneous emission in a semiconductor injection laser has an important effect on the response of to step current. Simple analytical approximations description transient response, also useful for study other current waveforms, are derived.
The principles of using radiating microstrip resonators as elements in a frequency scanning antenna array are described. cascade-coupled. This gives scan the main lobe due to phase-shift resonator addition that created by transmission line phase-shift. Experimental results <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</tex> -band, good agreement with theory, show it is possible an angle...
Investigation of the rate equations a semiconductor laser suggests that bit rates 3-4 Gbit/s can be achieved. Delay, ringing transients, and charge-storage effects removed by adjusting dc-bias current peak width pulse to values prescribed simple analytical expressions. Also, approximate formulas for light maximum, width, delay, integrated are given.
Narrow stripe lasers ( <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2-6 \mu</tex> m) and transverse junction exhibit excellent linearity. The dependence of relative second-and third-harmonic distortion is investigated as a function modulation frequency current. Relative second- -50 -70 dB observed for an optical signal 4 mW p-p xmlns:xlink="http://www.w3.org/1999/xlink">f_{m} = 60</tex> MHz). Intermodulation products are compared with the...
The dynamic and spectral behavior of the semiconductor stripe laser has been investigated. For this purpose rate equations have generalized to include several longitudinal transversal modes, spontaneous emission into active position dependence electron density through a term describing charge-carrier diffusion in plane layer. parameters used for solving these are found by theoretical experimental considerations. results show broadening spectrum together with significant content higher order...
G protein-coupled receptors (GPCRs) play an important role in many cellular responses; as such, their mechanism of action is utmost interest. To gain insight into the active conformation GPCRs, X-ray crystal structures nanobody (Nb)-stabilized β2 -adrenergic receptor (β2 AR) have been reported. Nb80, particular, able to bind intracellular protein binding site AR and stabilize conformation. Within complementarity-determining region 3 (CDR3) responsible for most interactions. Hence, we...
Herein, we report the development of bitopic ligands aimed at targeting orthosteric binding site (OBS) and a metastable (MBS) within same receptor unit. Previous molecular dynamics studies on ligand to β2-adrenergic (β2AR) suggested that pause transient, less-conserved MBSs. We envisioned MBSs can be regarded as allosteric sites targeted by homobivalent linking two identical pharmacophores. Such were designed based docking antagonist (S)-alprenolol into OBS an MBS synthesized....
Metastable binding sites (MBS) have been observed in a multitude of molecular dynamics simulations and can be considered low affinity allosteric (ABS) that function as stepping stones the ligand moves toward orthosteric site (OBS). Herein, we show MBS utilized ABS design, resulting ligands with improved kinetics. Four homobivalent bitopic (1–4) were designed by docking (S)-alprenolol ((S)-ALP) cocrystal structure β2 adrenergic receptor (β2AR) bound to antagonist ALP. Ligand 4 displayed...
A series of Gs protein peptidomimetics were designed and synthesised based on the published X-ray crystal structure active state β2-adrenergic receptor (β2AR) in complex with (PDB 3SN6). We hypothesised that such may function as allosteric modulators target intracellular binding site β2AR. Peptidomimetics to mimic 15 residue C-terminal α-helix pre-organised a helical conformation by (i, i + 4)-stapling using copper catalysed azide alkyne cycloaddition. Linear stapled analysed circular...
The results of two separate measurement setups to investigate GSM-link quality dependence on radio dispersion in rural Faroese and Danish environments, a repetitive GSM-data burst sequence system, correlation sounder are presented. Both operated the 900 MHz band. It is shown that GSM system performance seems be sensitive Q16 both below above specified value 9 dB, while delay spread minor influence when infinite. error distribution quite unsensitive interleaving for BER <10% vehicle speeds 40...
Measurements of the active properties a Dayem micro-bridge at X-band frequencies is described. The bridge was mounted in microwave cavity designed to match properly and output from detected using sensitive spectrometer. Microwave power freely running Josephson oscillations with dc-biased emit receiver frequency maximum extracted order 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-12</sup> W when tuned resonance. With an external...
Measurements of the residual surface resistance superconducting lead cavities as a function time during period month showed an oscillating variation. An explanation ageing curves is proposed.
Experimental and theoretical investigations have shown that the static, dynamic, spectral small-signal behaviour of semiconductor injection stripe lasers in a simple way can be interpreted by wavelength-dependent multimode rate equations. Simple analytical expressions for description laser are given.
An investigation of machined superconducting lead cavities operating in the circular cylindrical TE <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">011</inf> mode at 34.8 GHz is reported. Measured values surface resistance and shift resonance frequency are presented compared with calculated values. Construction criteria for high-Q proposed, based on a discussion different loss mechanisms cavity. According to these 10 were processed investigated...
An analysis of a lossy coupling mechanism is presented. It found that the reciprocal internal Q factor augmented by contribution (1 /2)/spl zeta/(l /Q/sub ex/), where /spl zeta/ depends on Parameters and Q/sub ex/ external factor. The theory applied to analyze superconducting high-Q cavity.
A software prediction tool for mobile radio channel impulse response estimation is presented. The simulation model based on the well known radar equation reflection from hillsides which can be treated as rough surfaces and therefore scattering power incoherently. In spite of simplicity agreements within a few dB between simulated measured responses at 980 MHz vertical polarisation are observed propagation in mixed mountain-sea environment. Comparison values useful parameters delay spread...
We report X-band microwave measurements on superconducting thin film micro-bridges (Dayem bridges), mounted in a half wavelength cavity with an adjustable coupling to match the bridge properly. Power emission from of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-13</sup> W MHz bandwidth was measured. Current noise fluctuations caused total voltage line width corresponding 150-200 MHz, when across swept through resonance; this we estimate...