Sökning: "shot-noise"

Visar resultat 1 - 5 av 16 avhandlingar innehållade ordet shot-noise.

  1. 1. Fluctuations in Mesoscopic Constrictions

    Författare :Jan Peter Hessling; Chalmers University of Technology; []
    Nyckelord :low frequency; fluctuations; quantum; noise; 1 f-noise; superconductivity; impurity; point contact; Andreev reflection; shot noise;

    Sammanfattning : In normal and superconducting quantum point contacts there are several sources of fluctuations. Thermally activated impurities in the vicinity of the junction cause the current (or voltage) to change with a typical frequency of the order of one Hz up to a few kHz. LÄS MER

  2. 2. Noise Properties of the Single Electron Transistor

    Författare :Serguei Kafanov; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Low-Frequency noise; Shot Noise; 1 f noise; Single Electron Transistor; charge sensitivity; SET; electrometer; Coulomb blockade; radio-frequency Single Electron Transistor; RF-SET;

    Sammanfattning : The Single Electron Transistor (SET) is a sensitive electrometer with a charge sensitivityultimately limited by noise. In this thesis we present measurements of noiseproperties and charge sensitivity of the radio-frequency Single Electron Transistor. LÄS MER

  3. 3. Development of Cryogenic Low Noise 4-8 GHz HEMT Amplifier and its Advanced Characterization

    Författare :Erik Sundin; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shot-noise; low noise amplifier; cryogenic amplifier; sis; noise measurement; HEMT;

    Sammanfattning : In most radio astronomy instrumentation, cryogenic low noise amplifiers (LNA) are used as intermediate frequency (IF) amplifiers. The system noise temperature is among the most important parameters of a receiver and requires state of the art components. LÄS MER

  4. 4. Parity Effects in Single Charge Tunneling

    Författare :Magnus Gisselfält; Chalmers University of Technology; []
    Nyckelord :mesoscopic; single charge tunneling; photon-assisted tunneling; shot noise; SET transistor; parity effect; Andreev tunneling; Coulomb blockade;

    Sammanfattning : The subject of this thesis is single charge tunneling effects, especially parity effects, as they are manifested in quantum mechanical tunneling through a metallic island small enough to cause single electrons to block tunneling of other electrons due to Coulomb interaction. When the island is superconducting the ground state energy depends on the parity of the number of electrons on the island: outside of the condensate there will always be at least one electron contributing to the energy for an odd number of electrons and this will have observable consequences. LÄS MER

  5. 5. Mid- and near-infrared NICE-OHMS : techniques for ultra-sensitive detection of molecules in gas phase

    Författare :Thomas Hausmaninger; Ove Axner; Kyle Crabtree; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; spectrometry; NICE-OHMS; trace gas detection; acetylene; methane; isotopologues; near-infrared; mid-infrared; shot-noise; optical parametric oscillator; teknisk fysik med inriktningen mikrosystemteknik; engineering science with specialization in microsystems technology;

    Sammanfattning : Noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is a technique for ultra-sensitive detection of molecular absorption and dispersion. For highest performance, the technique combines cavity enhancement (CE) with frequency modulation (FM); while the former increases the effective interaction length between the light and the analyte by several orders of magnitudes, the latter removes the in-coupling of 1/f noise and makes the signals background free. LÄS MER