Application of the Mössbauer effect to the study of subnanometer harmonic displacements in thin solids

Abstract

We measure subnanometer displacements of thin samples vibrated by piezotransducer. Samples contain 57 Fe nuclei, which are exposed to 14.4 keV γ-radiation. Vibration produces sidebands from a single absorption line of the sample. The sideband intensities depend on the vibration amplitude and its distribution along the sample. We developed a model of this distribution, which adequately describes the spectra of powder and stainless steel (SS) absorbers. We propose to filter γ-radiation through a small round hole in the lead mask, placed before the absorber. In this case only a small spot of the vibrated absorber is observed. We found for SS foil that nuclei, exposed to γ-radiation in this small spot, vibrate with almost the same amplitudes whose difference does not exceed a few picometers within the irradiated area.

Mössbauer Method for Studying Vibrations in a Granular Medium Excited by Ultrasound

“…In this paper we present the results of our new experiments with sodium ferrocyanide K 4 Fe(CN) 6 ·3H 2 O. In the previous report [14] we worked with the pressed powder of this salt. In the experiments, which we report here, powder crystals of sodium ferrocyanide were grind up and stirred in epoxy resin without hardener.…”

“…Vibrations of SS foil were studied in Refs. [14,15]. There, it was shown that SS foil vibrates as a whole (piston like).…”

Pulse shaping by a frequency filtering of a sawtooth phase-modulated cw laser

“…A different method of pulse compression was recently reported in [15][16][17][18]. The capabilities of this method was experimentally demonstrated for gamma photons with long duration of a single-photon wave packet [15,16].…”

“…The method [15,16] is also based on frequency modulation of the radiation field. However, in spite of subsequent phasing of the produced spectral components, absorption (removal) of a particular spectral component is used [15][16][17]. This removal method has many in common with other methods used before.…”

“…The method is also flexible and allows fine control of the duration and repetition rate of the pulses. An appreciable shortening of the pulses [16,17] is achieved for high phase-modulation index as in the previous passive methods of the pulse shaping.…”