Low-temperature dynamics of incommensurate biphenyl as probed by spectral hole burning

A. Suisalu; V. Zazubovich; J. Kikas; J. Friebel; J. Friedrich

doi:doi:10.1209/epl/i1998-00517-6

DOI: 10.1209/epl/i1998-00517-6

Europhys. Lett, 44 (5), pp. 613-619 (1998)

Low-temperature dynamics of incommensurate biphenyl
as probed by spectral hole burning

A. Suisalu ¹, V. Zazubovich ^1,2, J. Kikas ², J. Friebel ³ and J. Friedrich ³

¹ Institute of Physics, Riia 142 - EE2400 Tartu, Estonia
² University of Tartu, Institute of Materials Science, Tähe 4 - EE2400 Tartu, Estonia
³ Technische Universität München, Lehrstuhl für Physik Weihenstephan
D-85350 Freising, Germany

(received 18 May 1998; accepted in final form 14 October 1998)

PACS. 61.44Fw - Incommensurate crystals.
PACS. 78.40 ${\rm -q}$ - Absorption and reflection spectra: visible and ultraviolet.
PACS. 33.70Jg - Line and band widths, shapes, and shifts.

Abstract:

We have measured the temperature dependence of the homogeneous width of spectral holes in the incommensurate phase III of chlorin-doped biphenyl from 60 mK to 10 K. Below 2 K a power law ( $\sim T^\alpha$ , $\alpha= 1.36, 1.74$ for different spectral peaks) prevails. Above 2 K a strong coupling to low-energy (5 and $\rm 9\; cm^{-1}$ ) vibrational modes dominates. No indication of a low-temperature lock-in transition was found.

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