Sökning: "Niobium Nitride"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden Niobium Nitride.

1. 1. Antenna Integrated Superconducting Mixers

   Författare :Hans Ekström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tapered slotline antenna; mixer; double dipole antenna; superconducting; hot electron; receiver; Niobium; bolometer; trilayer junction; edge junction; Niobium Nitride; SIS;

   Sammanfattning : This thesis investigates the prospects of some different superconducting mixers integrated with planar antennas for the millimeter and submillimeter regime. Two kinds of Superconductor/Insulator/Superconductor (SIS) tunnel junctions for use in mixers have been fabricated; Nb/PbBi edge junctions and Nb trilayer junctions. LÄS MER

3. 2. Ultra-thin Niobium Nitride Films for Hot Electron Bolometer and THz Applications

   Författare :Sascha Krause; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; HEB; ultra-thin NbN;

   Sammanfattning : The part of the electromagnetic spectrum between microwaves and infrared, also known as the terahertz band, is of particular interest for radio astronomy. The radiation intensity of the cold universe peaks at this frequency band, thus defining the demand on sensitive low-noise instruments in this particular frequency range. LÄS MER

4. 3. GaN-based HEMTs for Cryogenic Low-Noise Applications

   Författare :Mohamed Aniss Mebarki; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cryogenic temperatures; superconductivity; RFI; High Electron Mobility Transistor HEMT ; Low Noise Amplifier LNA ; Niobium Nb ; Radio-astronomy; Gallium Nitride GaN ; high frequency;

   Sammanfattning : Radio-astronomy deals with signals and radiations of extremely weak intensity. Also, it requires robust and rugged technologies able to sustain and prevent the Radio Frequency Interferences (RFI). LÄS MER

5. 4. Investigation of electrochemical properties and performance of stimulation/sensing electrodes for pacemaker applications

   Författare :Anna Norlin; Jinshan Pan; Dieter Scharnweber; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; pacemaker electrode; interfacial property; biomaterial; electrostimulation charge transfer mechanism; electrochemical impedance spectroscopy; transient processes; plasma electrolysis anodisation; porous niobium oxide; ruthenium oxide; nano-porous carbon; iridium oxide; titanium nitride; platinum; surface roughness; porous electrode; pacing impedance; electrode polarisation; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : People suffering from certain types of arrhythmia may benefit from the implantation of a cardiac pacemaker. Pacemakers artificially stimulate the heart by applying short electrical pulses to the cardiac tissue to restore and maintain a steady heart rhythm. By adjusting the pulse delivery rate the heart is stimulated to beat at desired pace. LÄS MER

7. 5. NbTiN for improved superconducting detectors

   Författare :Julien Zichi; Val Zwiller; Gregory Gol'tsman; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; superconducting nanowire sngle photon detector; SNSPD; niobium titanium nitride; NbTiN; reactive co-sputtering; quantum communications; quantum sensing; Fysik; Physics;

   Sammanfattning : The physics of single photons is fascinating, by manipulating them we can observe and probe quantum effects. Doing so requires the fabrication and utilization of single photon sources, of which many types have been developed including quantum dots, trapped atoms and ions, and color centers. LÄS MER