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We present a theoretical investigation on new and interesting properties of the phonon polarization field in solids. In particular, non-classical aspects of the phonon population and an experimental scheme that would enable one to detect them will be discussed.
For a large variety of superconducting materials both experimental and theoretical lattice dynamical studies have been performed to date. The assignment of the observed infrared- and Raman-active phonon modes to the particular lattice eigenmodes is generally accepted. We will concentrate here upon the analysis of the changes of the infrared-phonon parameters (frequency and linewidth) upon entering the superconducting state which, as will be shown, may provide information on the magnitude of the superconductivity-related gap and its dependence on the superconducting transition temperature Tc.
The mechanics of phonon transport in membrane-isolated superconducting transition edge sensors is discussed. Surveys of the literature on this type of sensor reveal a number of designs with excess heat capacity and a smaller subset that exhibit decoupling of the superconducting film from the underlying dielectric. A simple model is addressed in which the membrane, despite its thermal isolation, fails to fully thermalize to the temperature of the metal film heating it. A population of phonons exists which is emitted by the metal film, partially thermalizes the dielectric and is then reabsorbed in the metal film without escaping from the device structure to the thermal bath. The size of this population and its contribution to the heat capacity are estimated for several device scenarios.
The mechanics of phonon transport in membrane-isolated superconducting transition edge sensors is discussed. Surveys of the literature on this type of sensor reveal a number of designs with excess heat capacity and a smaller subset that exhibit decoupling of the superconducting film from the underlying dielectric. A simple model is addressed in which the membrane, despite its thermal isolation, fails to fully thermalize to the temperature of the metal film heating it. A population of phonons exists which is emitted by the metal film, partially thermalizes the dielectric and is then reabsorbed in the metal film without escaping from the device structure to the thermal bath. The size of this population and its contribution to the heat capacity are estimated for several device scenarios.
Kinetic inductance detectors (KID) have received increased interest due to their relative ease of fabrication, low noise, and scalability to large format arrays required by next generation of astronomical telescopes. The development of KIDs has progressed rapidly, with very low noise equivalent power demonstrated by several groups and KIDs arrays implemented in several ground-based and air-borne instruments. In this paper, we describe a new fabrication process which consists of a membrane isolated KID incorporating a phononic bandgap structure tuned to block recombination phonons from escaping to the thermal bath. This architecture is designed to increase the quasi-particle lifetime and results in increased responsivity to signal photons and lower noise. These devices have been fabricated as lumped-element resonators with hafnium inductors and Nb capacitors on low stress silicon nitride and silicon-on-insulator membranes. We discuss the fabrication process, which uses a combination of sub-micron laser based direct write lithography and nanoscale electron beam lithography.
Electron-phonon attenuation measured in indium arsenide and gallium arsenide single crystals at 10 Kmc and 10 mc as function of temperature
Plasma theory of electron-phonon interaction
Phonon induced relaxation in excited optical states of trivalent praseodymium in lanthanum fluoride
Phonon drag thermopower in copper-aluminum and copper-silicon alloys
Electron-phonon interaction in III-V SEMICONDUCTOR crystals - attenuation measurements in indium antimonide single crystals
Phonon-drag thermopower change in Cu-Al and Cu-Si alloys at cryogenic temperature
Electron-phonon interaction in III to V semiconductors and temperature dependence of attenuation in quartz and tourmaline
Phonon-drag thermopower change in dilute copper alloys used to determine numerical values for scattering parameter
Transducer techniques for generating acoustic waves evaluated in study of electron-phonon interactions in semiconductors
Two-phonon absorption in ultrasonic paramagnetic resonance of uranium-doped calcium fluoride, relating wave attenuation to ultrasonic intensity and magnetic field angular variation
Recent paper has raised again a question about the electron-phonon (EP) relaxation rate in impure metals. From weak localization (WL) measurements the authors have found that the dephasing rate in AuPd disordered films follows the T(sup 2)el-law (el is the mean free path).
Spontaneous Cerenkov-like phonon emission by charged particle moving through piezoelectric solid
Two-phonon Raman scattering in cubic crystals, noting use of polarization effect to determine active irreducible representations