Abstract
The light scattering work on pyroelectric BaMnF4 is reassessed here in view of new structural information on the incommensurate phase. The dispersions in the acoustic phonon velocities Vcb and Vcc are ascribed to coupling to the phason and amplitudon, respectively; the failure to observe a true soft mode in the Raman spectrum for T < Ti ≃ 247 K is attributed to the overdamped nature of the amplitudon even for T ≃ 85 K; the static central peak is associated with symmetry breaking frozen defects; and the dynamic central peak previously thought to be due to the phason is now assigned to LA-phonon — amplitudon coupling. Thus the light scattering experiments have provided no direct evidence for phasons or amplitudons. It is suggested that Brillouin scattering experiments should be performed on incommensurate ThBr4, which is a very simple system with small phason and amplitudon damping, to search for the overdamped phason and predicted amplitudon — acoustic-phonon coupling. Finally, it is demonstrated that quasiperiodic superlattices provide exciting possibilities for detailed comparisons between theory and experiment.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
See the review by T. Matsubara, Jpn. J. Appl. Phys. 24, suppl. 24-2, 1 (1985).
J. Petzelt, Phase Transitions 2, 155 (1981).
H. Z. Cummins and A. P. Levanyuk, eds., “Light Scattering Near Phase Transitions” (North-Holland, Amsterdam, 1983).
V. A. Golovko and A. P. Levanyuk, Sov.-Phys. JETP 54, 1217 (1981).
R. Zeyher and W. Finger, Phys. Rev. Lett. 49, 1833 (1982).
V. A. Golovko and A. P. Levanyuk in Ref. 3, Chapt. 3.
R. V. Pisarev, B. B. Krichevtzov, P. A. Markovin, O. Yu. Korshunov and J. F. Scott, Phys. Rev. B28, 2667 (1983).
T. W. Ryan, J. Phys. C19, 1097 (1986).
P. Saint-Grégoire, R. Almairac, A. Freund and J. Y. Gesland, Ferroelectrics 67, 15 (1986).
See, for example, reviews by J. F. Scott in Rep. Prog. Phys. 12, 1055 (1979); Ferroelectrics 24, 127 (1980); in Ref. 3, Chapt. 5; and Ferroelectrics 66, 11 (1986).
D. E. Cox, S. M. Shapiro, R. A. Cowley, M. Eibschütz and H. J. Guggenheim, Phys. Rev. B19, 5754 (1979).
D. E. Cox, S. M. Shapiro, R. J. Nelmes, T. W. Ryan, H. J. Bleif, R. A. Cowley, M. Eibschütz and H. J. Guggenheim, Phys. Rev. B28, 1640 (1983).
M. Barthès-Régis, R. Almairac, P. St-Grégoire, C. Filippini, U. Steigenberger, J. Nouet and Y. Gesland, J. Physique Lett. 44, L829 (1983).
P. St-Grégoire, M. Barthes, R. Almairac, J. Nouet, J. Y. Gesland, C. Fillippini and U. Steigenberger, Ferroelectrics 53, 307 (1984).
B. B. Lavrencic and J. F. Scott, Phys. Rev. B24, 2711 (1981).
V. Dvorak and J. Fousek, Phys. Stat. Sol. A61, 99 (1980).
J. F. Ryan and J. F. Scott, Solid State Commun. 14, 5 (1974) and in “Light Scattering in Solids,” M. Balkanski, R. C. C. Leite and S. P. S. Porto, eds. (Flammarion, Paris, 1976), p. 761
V. V. Eremenko, A. P. Mokhir, Yu. A. Popkov and O. L. Reznitskaya, Ukr. Fiz. Zh. 20, 146 (1975).
Yu. A. Popkov, S. V. Petrov and A. P. Mokhir, Sov. J. Low Temp. Phys. 1, 91 (1975).
D. W. Bechtle and J. F. Scott, J. Phys. C. 10, L209 (1977).
D. W. Bechtle, J. F. Scott and D. J. Lockwood, Phys. Rev. B18, 6213 (1978).
K. B. Lyons and H. J. Guggenheim, Solid State Commun. 31, 285 (1979).
A. F. Murray and D. J. Lockwood in “Proc. 7th Int. Conf. Raman Spectrosc”, W. F. Murphy, ed. (North-Holland, Amsterdam, 1980), p. 58.
K. B. Lyons, T. J. Negran and H. J. Guggenheim, J. Phys. C13, L415 (1980).
D. J. Lockwood, A. F. Murray and N. L. Rowell, J. Phys. C14, 753 (1981).
A. F. Murray, G. Brims and S. Sprunt, Solid State Commun. 39, 941 (1981).
K. B. Lyons, R. N. Bhatt, T. J. Negran and H. J. Guggenheim, Phys. Rev. B25, 1791 (1982).
A. D. Bruce and R. A. Cowley, J. Phys. C11, 3609 (1978).
See comments by J. F. Scott, in Ref. 3, Chapt. 5.
See the review by M. V. Klein, in Ref. 3, Chapt. 8.
A. A. Volkov, G. V. Kozlov, S. P. Lebedev, J. Petzelt and Y. Ishibashi, Ferroelectrics 45, 157 (1982).
J. Petzelt and V. Dvorak, J. Phys. C9, 1587 (1976).
I. J. Fritz, Phys. Lett. 51A, 219 (1975).
See J. F. Scott, Ferroelectrics 47, 33 (1983).
W. Taylor, D. J. Lockwood and H. Vass, Solid State Commun. 27, 547 (1978).
B. I. Halperin and C. M. Varma, Phys. Rev. B14, 4030 (1976).
J. F. Scott, private communication.
T. W. Ryan, R. A. Cowley and S. R. Andrews, J. Phys. C19, L113 (1986).
The crystals were grown from zone melted materials by H. J. Guggenheim at Bell Laboratories.
L. Bernard, R. Currat, P. Delamoye, C. M. E. Zeyen, S. Hubert and R. de Kouchkovsky, J. Phys. C16, 433 (1983).
C. M. E. Zeyen, Physica 120B, 283 (1983).
S. Hubert, P. Delamoye, S. Lefrant, M. Lepostollec and M. Hussonnois, J. Solid State Chem. 36, 36 (1981).
R. Merlin, K. Bajema, R. Clarke, F.-Y. Juang and P. K. Bhattacharya, Phys. Rev. Letters 55, 1768 (1985).
See the article by R. Clarke in these Proceedings, p. 357.
M. W. C. Dharmawardana, D. J. Lockwood, J.-M. Baribeau and D. C. Houghton, Phys. Rev. B34, 3034 (1986).
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1987 Plenum Press, New York
About this chapter
Cite this chapter
Lockwood, D.J. (1987). Light Scattering from Incommensurate Insulators; Mainly BaMnF4. In: Scott, J.F., Clark, N.A. (eds) Incommensurate Crystals, Liquid Crystals, and Quasi-Crystals. NATO ASI Series, vol 166. Springer, New York, NY. https://doi.org/10.1007/978-1-4757-0184-5_10
Download citation
DOI: https://doi.org/10.1007/978-1-4757-0184-5_10
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4757-0186-9
Online ISBN: 978-1-4757-0184-5
eBook Packages: Springer Book Archive