Abstract
Abstract
Quasicrystals (QCs) have a peculiar structural order characterized by quasiperiodicity and non-crystallographical point group symmetry. To reveal their characteristic physical property reflecting the peculiar structural order, specific heat measurements were performed for Al–Pd–Mn icosahedral QCs (i-QCs) and a series of crystal approximants (CAs) of 2/1- 1/1- and 1/0-cubic types at 400–1200 K. The measured specific heat per atom at constant pressure
c
P
was converted to that at constant volume
c
V
by using data of the thermal expansion coefficient and bulk modulus. Below ∼700 K, the
c
V
values of all the specimens of i-QCs and CAs were close to
3
k
B
(
k
B
:
Boltzman’s constant), i.e., they obeyed Dulong–Petit’s law. With further increase in temperature, the i-QCs showed a dramatic increase in
c
V
with increasing temperature, and reached
5
k
B
at 1100 K. In contrast, the 2/1 CAs showed a similar but slightly smaller increase in
c
V
,
whereas the 1/1 and 1/0 CAs showed a negligible increase. The systematic behavior of
c
V
in the order of CAs and QC demonstrates that a large excessive specific heat is a characteristic feature of QCs, reflecting the peculiarity of their structural order. Its possible physical mechanism was discussed in terms of anharmonic atomic vibrations, electronic excitations, and phasonic excitations.
Funder
Japan Society for the Promotion of Science
Subject
General Physics and Astronomy
Cited by
8 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献