Sökning: "phonons"

Visar resultat 1 - 5 av 16 uppsatser innehållade ordet phonons.

  1. 1. Phonons in 1-D Graphene Nanoribbons Probed with Raman Spectroscopy : Unraveling Fundamental Properties in 9-atom-wide Graphene Nanoribbons

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Angel Victor Labordet Alvarez; [2023]
    Nyckelord :9-armchair graphene nanoribbons 9-AGNRs ; polarization Raman Spectroscopy PRS ; temperature-dependent Raman spectroscopy; thermal sensitivity; thermal stability; Grüneisen parameter χ ; anharmonicities; vibrational modes G; D; RBLM .; 9-armchair grafen nanoribbons 9-AGNRs ; polarisation Raman spektroskopi PRS ; temperaturberoende Raman spektroskopi; termisk känslighet; termisk stabilitet; Grüneisen parameter χ ; anharmoniciteter; vibrationslägen G; D; RBLM .;

    Sammanfattning : This report employs advanced Raman spectroscopy techniques to investigate the fundamental properties of 9-AGNRs comprehensively. It is divided into two main sections addressing distinct aspects of 9-AGNR behavior. In the first section, Polarization Raman spectroscopy (PRS) probes phonon mode symmetries in 9-AGNRs. LÄS MER

  3. 2. Towards a tunable, wide-band acoustic transducer operating in the quantum regime.

    Master-uppsats, KTH/Tillämpad fysik

    Författare :Abel Hugot; [2022]
    Nyckelord :Hybrid quantum systems; Acoustics; Impedance matching; SQUIDs; Hybrida kvantsystem; Akustik; Impedansanpassning; SQUIDs.;

    Sammanfattning : In the past decade we have seen fast development of new quantum technologies that promise to revolutionise communications and computing. Many different routes are explored to physically implement such quantum technologies. Among others, we can mention superconducting circuits, spin-based devices and photonic devices. LÄS MER

  4. 3. Time-resolved x-ray diffraction study of longitudinal optical phonons in zincblende semiconductors

    Master-uppsats, Lunds universitet/Atomfysik; Lunds universitet/Fysiska institutionen

    Författare :Lassi Linnala; [2022]
    Nyckelord :femtosecond THz radiation; ultrafast x-ray diffraction; pump-probe; longitudinal optical phonons; zincblende semiconductors; anharmonic decay; density functional perturbation theory; Physics and Astronomy;

    Sammanfattning : Anharmonic decay of longitudinal optical (LO) phonons in zincblende semiconductors is not at present well characterized due to the polar and many-body nature of the problem. Femtosecond THz radiation offers a novel route to this study, as the interaction of this radiation is directly with the phonon lattice and these THz excited phonons do not have enough energy to excite electrons over the band gap. LÄS MER

  5. 4. Synthesis and thermoelectric properties of Cr1-xMexN (Me = Mo, V)

    Master-uppsats, Linköpings universitet/Tunnfilmsfysik

    Författare :Victor Rutberg; [2022]
    Nyckelord :Chromium nitride; thin films; thermoelectrics; physical vapour deposition; medium entropy alloy;

    Sammanfattning : Among emerging materials systems for thermoelectric applications, the early transition-metal nitrides based on ScN and CrN show unexpectedly promising properties. These properties are determined by high Seebeck coefficient, low thermal conductivity, and high electrical conductivity. LÄS MER

  7. 5. Quantum thermodynamics explorations with a Hubbard-Holstein dimer

    Kandidat-uppsats, Lunds universitet/Matematisk fysik; Lunds universitet/Fysiska institutionen

    Författare :Emil Adam Jonatan Östberg; [2021]
    Nyckelord :QTD Quantum Thermodynamics Hubbard-Holstein Hubbard Holstein dimer Lanczos Suzuki-Trotter ST Exact diagonalization ED Hysteresis Path dependence Battery Mott-insulator; Physics and Astronomy;

    Sammanfattning : The goal of this project is to characterize the quantum thermodynamics of a Hubbard-Holstein dimer. We explore how the standard formalism of quantum thermodynamics behaves in the context many-body physics. LÄS MER