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Publication Type: search.filters.UBSTyp.KonferenzbeitragSubject: search.filters.subject.530Author: search.filters.author.Lassmann, KurtAuthor: search.filters.author.Groß, Peter

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Now showing 1 - 4 of 4
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    Phono-conduction spectroscopy of shallow states in semiconductors
    (1990) Lassmann, Kurt; Gienger, Martin; Groß, Peter
    Phonoconduction spectroscopy of shallow states in semiconductors by help of superconduction Al-junctions as phonon sources with high spectral resolution is a sensitive new technique with phonon frequencies well up in the Debye range. The large k-vector of the phonons involved opens new possibilities for the investigation of electron dynamics and states in semiconductors.
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    One-phonon ionization of neutral donors in germanium
    (1989) Gienger, Martin; Groß, Peter; Lassmann, Kurt
    Here we show by phonon spectroscopy with superconducting tunnelling junctions that one-phonon excitations from the ground state to the conduction band (CB) are measurable as phonon induced conductivity (PIC) changes in the special case of donors in Ge. For the conductivity thresholds we find somewhat smaller binding energies than evaluated from optical measurements whereas for the 1s-singlet to 1s-triplet ground state splitting as seen by elastic phonon scattering we obtain the optical values.
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    Investigation of A+-states in Si and Ge by phonon-induced conduction under uniaxial stress
    (1993) Groß, Peter; Lassmann, Kurt
    By the analysis of the stress dependence of phonon induced conductivity (PIC) with superconducting Al-tunneling junctions as phonon generators we have now found strong evidence for a split ground state in the cases Si:Ga+, Si:Al+ and Ge:Zn+.
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    Depopulation effects in the phonoconduction response of A+ -states in silicon and germanium
    (1990) Groß, Peter; Gienger, Martin; Lassmann, Kurt
    We show here that deviations from these assumptions are effective in the experiment and responsible in particular for the observed illumination dependence of the phonoconduction signal. The phonon spectrum of an Al - STJ at bias V = eU > 2ΔAl consists of a continuum with a sharp threshold at Ώm = V - 2ΔAl. In the differentiated spectrum Ώm becomes the most prominent bias-tunable feature, namely the quasimonochromatic line of phonon spectroscopy used for the approximate analysis of sharp phonon scattering resonances such as the OI line of Fig. 1a (which shows inversion of the center due to strong scattering).