MEASUREMENT OF THE PHONON-FRACTON CROSSOVER IN THE DENSITY OF STATES OF SILICA AEROGELS

被引：22

作者：

COURTENS, E

LARTIGUE, C

MEZEI, F

VACHER, R

CODDENS, G

FORET, M

PELOUS, J

WOIGNIER, T

机构：

[1] HAHN MEITNER INST KERNFORSCH BERLIN GMBH, W-1000 BERLIN 39, GERMANY

[2] UNIV MONTPELLIER 2, SCI MAT VITREUX LAB, F-34060 MONTPELLIER, FRANCE

[3] CENS, CNRS, CEA, LAB LEON BRILLOUIN, F-91191 GIF SUR YVETTE, FRANCE

来源：

ZEITSCHRIFT FUR PHYSIK B-CONDENSED MATTER | 1990年 / 79卷 / 01期

关键词：

D O I：

10.1007/BF01387817

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

The density of vibrational states in a fractal silica aerogel of Hausdorff dimension D≃2.4 has been determined using spin-echo neutron spectroscopy. A smooth phonon-fracton crossover is found with a fracton spectral dimension of {Mathematical expression}. This direct measurement of {Mathematical expression} near crossover agrees with a previous finding based on scaling Brillouin-spectroscopy results obtained with several samples. We also show that protons adsorbed in the gel vibrate with substantially higher amplitude than the silica matrix. © 1990 Springer-Verlag.

引用

页码：1 / 2

页数：2

共 13 条

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