|
Эта публикация цитируется в 21 научных статьях (всего в 21 статьях)
КОНДЕНСИРОВАННОЕ СОСТОЯНИЕ
Quantum bicriticality in Mn$_{1-x}$Fe$_{x}$Si solid solutions:
exchange and percolation effects
S. V. Demishevab, I. I. Lobanovaab, V. V. Glushkovab, T. V. Ishchenkoa, N. E. Sluchankoa, V. A. Dyadkinc, N. M. Potapovac, S. V. Grigor'evc a A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow
b Moscow Institute of Physics and Technology
c B. P. Konstantinov Petersburg Nuclear Physics Institute, Russian Academy of Sciences
Аннотация:
The $T{-}x$ magnetic phase diagram of Mn$_{1-x}$Fe$_x$Si
solid solutions is probed by magnetic susceptibility, magnetization and
resistivity measurements. The boundary limiting phase with short-range
magnetic order (analogue of the chiral liquid) is defined experimentally and
described analytically within simple model accounting both classical and
quantum magnetic fluctuations together with effects of disorder. It is shown
that Mn$_{1- x}$Fe$_x$Si system undergoes a sequence of two quantum phase
transitions. The first "underlying" quantum critical (QC) point $x^*\sim
0.11$ corresponds to disappearance of the long-range magnetic order. This
quantum phase transition is masked by short-range order phase, however, it
manifests itself at finite temperatures by crossover between classical and
quantum fluctuations, which is predicted and observed in the paramagnetic
phase. The second QC point $x_c\sim 0.24$ may have topological nature and
corresponds to percolation threshold in the magnetic subsystem of Mn$_{1-
x}$Fe$_x$Si. Above $x_c$ the short-range ordered phase is suppressed and
magnetic subsystem becomes separated into spin clusters resulting in
observation of the disorder-driven QC Griffiths-type phase characterized
by an anomalously divergent magnetic susceptibility $\chi\sim 1/T^\xi$ with
the exponents $\xi\sim 0.5{-} 0.6$.
Поступила в редакцию: 08.11.2013
Образец цитирования:
S. V. Demishev, I. I. Lobanova, V. V. Glushkov, T. V. Ishchenko, N. E. Sluchanko, V. A. Dyadkin, N. M. Potapova, S. V. Grigor'ev, “Quantum bicriticality in Mn$_{1-x}$Fe$_{x}$Si solid solutions:
exchange and percolation effects”, Письма в ЖЭТФ, 98:12 (2013), 933–937; JETP Letters, 98:12 (2013), 829–833
Образцы ссылок на эту страницу:
https://www.mathnet.ru/rus/jetpl3617 https://www.mathnet.ru/rus/jetpl/v98/i12/p933
|
Статистика просмотров: |
Страница аннотации: | 204 | PDF полного текста: | 61 | Список литературы: | 34 | Первая страница: | 2 |
|