Thermally activated and quantum plasticity of solid<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>He</mml:mi><mml:mprescripts /><mml:none /><mml:mn>3</mml:mn></mml:mmultiscripts></mml:math>at temperatures below 0.5 K

Lisunov, A. A.; Maı̆danov, V. A.; Rubanskyi, V. Yu.; Rubets, S. P.; Rudavskiı̆, É. Ya.; Smirnov, S. N.; Zhuchkov, V. A.

doi:10.1103/physrevb.92.140505

Cited by 15 publications

(3 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…В обычных металлах квантовые эффекты заметны в области нагрузок близких к критическому напряжению, так называемому напряжению Пайерлса τ P , когда барьеры значительно скомпенсированы. Так, например, при движении дислокаций по системе скольжения (100) 010 в β−Sn, согласно данным работы [29] критическое напряжение составляет τ P = 1.2 • 10 7 Pa, температура перехода T c = 3.3 K при напряжении τ P − τ ≈ 10 6 Pa. Наблюдение подобных эффектов при промежуточных нагрузках, к которым относится расчет настоящей работы, в большей степени возможно в так называемых квантовых кристаллах, таких как твердый гелий [30,31], LiH [32] (с интерпретацией в [33]) и ряд других [4].…”

Section: заключениеunclassified

Активационно-Туннельная Динамика Протяженных Систем В Периодическом Потенциальном Рельефе

Петухов¹

2021

Физика Твердого Тела

View full text Add to dashboard Cite

The dynamics of systems in barrier structures is determined by the rate of fluctuation decay of metastable states in intermediate minima of the potential relief. When the temperature decreases, thermal fluctuations freeze out and are replaced by quantum ones, which leads to a kind of phase transition in the dynamics. The nature of this transition in various systems is analogous to either the second or first kind of transition. The transition temperature depends on the degree of metastability, and can be controlled by an external load. The purpose of this work is to calculate this dependence for an extended system in a tilted periodic relief of the "washboard" type in a wide range of load changes.

show abstract

Section: заключениеunclassified

Активационно-Туннельная Динамика Протяженных Систем В Периодическом Потенциальном Рельефе

Петухов¹

2021

Физика Твердого Тела

View full text Add to dashboard Cite

show abstract

“…In the dynamic properties of these systems a transition from a strong temperature dependence to an athermic behavior is often observed with a decrease in temperature. In particular, at suciently low temperatures the quantum athermic plasticity is observed in a wide range of materials, among the numerous works on this subject we mention only some [2][3][4][5][6]. The observation of non-classical rotational inertia in solid 4 He [7] caused a new surge of interest in quantum crystals [8] and the previously predicted [9] features of the quantum dynamics of defects in them.…”

Section: Introductionmentioning

confidence: 99%

Quantum mechanical tunnel nucleation of kink-solitons in a random potential

Petukhov¹

2018

J. Stat. Mech.

View full text Add to dashboard Cite

In connection with the development of nanotechnology, the sizes of the objects under study have approached the values at which the fundamental quantum mechanical laws of dynamics come into play. An important component of such dynamics in extended systems is the process of domain formation and propagation of their boundaries. In quasi-one-dimensional systems, these boundaries are peculiar quasiparticles—topological kink-solitons or simply kinks. Various processes such as switching states or phase transformations of a system can be described in terms of nucleation and propagation of kinks. With decreasing temperature, the thermal activation mechanism of nucleation of kinks is replaced by quantum mechanical subbarrier tunneling. The insufficient perfection of materials imposes often uncontrolled perturbations that modify the regularities of the tunnel formation of kinks. The influence of perturbations of the type of spatial ‘Gaussian noise’ is modeled in the work. The distribution of the rate of quantum mechanical tunnel nucleation of kinks over realizations of random fields is studied. It is shown that even relatively weak perturbations, as compared to the threshold of metastability, lead to a wide spectrum of kink nucleation times and a significant modification of the dependence of their typical characteristics on the driving force.

show abstract

“…It means that to explain the low-temperature anomalies in thermodynamics of the pure 4 He lattice we have to propose a model which based essentially on its hcp crystallography. The contribution from dislocations into observable properties of solid helium is a subject of extensive studies over last years [27][28][29][30], but it is very difficult to obtain some direct evidence of the dislocations response in such systems because of specifics of helium crystals prepared in restricted volume under external pressure at ultralow temperature.…”

Section: Introductionmentioning

confidence: 99%

Thermodynamics of dilute 3He–4He solid solutions with hcp structure

Chishko

2018

Low Temperature Physics

View full text Add to dashboard Cite

To interpret the anomalies in heat capacity C V (T) and temperature-dependent pressure P(T) of solid hexagonal close-packed (hcp)4He we exploit the model of hcp crystalline polytype with specific lattice degrees of freedom and describe the thermodynamics of impurity-free 4 He solid as superposition of phononic and polytypic contributions. The hcp-based polytype is a stack of 2D basal atomic monolayers on triangular lattice packed with arbitrary long (up to infinity) spatial period along the hexagonal c axis perpendicular to the basal planes. It is a crystal with perfect ordering along the layers, but without microscopic translational symmetry in perpendicular direction (which remains, nevertheless, the rotational crystallographic axis of third order, so that the polytype can be considered as semidisordered system). Each atom of the hcp polytype has twelve crystallographic neighbors in both first and second coordination spheres at any arbitrary packing order. It is shown that the crystal of such structure behaves as anisotropic elastic medium with specific dispersion law of phonon excitations along c axis. The free energy and the heat capacity consist of two terms: one of them is a normal contribution (with C V (T)  T 3 ) from phonon excitations in an anisotropic lattice of hexagonal symmetry, and another term (an "excessive" heat) is a contribution resulted by packing entropy from quasi-one-dimensional system of 2D basal planes on triangular lattice stacked randomly along c axis without braking the closest pack between neighboring atomic layers. The excessive part of the free energy has been treated within 1D quasi-Ising (lattice gas) model using the transfer matrix approach. This model makes us possible to interpret successfully the thermodynamic anomaly (heat capacity peak in hcp 4 He) observed experimentally.

show abstract

Thermally activated and quantum plasticity of solidHe3at temperatures below 0.5 K

Cited by 15 publications

References 19 publications

Активационно-Туннельная Динамика Протяженных Систем В Периодическом Потенциальном Рельефе

Активационно-Туннельная Динамика Протяженных Систем В Периодическом Потенциальном Рельефе

Quantum mechanical tunnel nucleation of kink-solitons in a random potential

Thermodynamics of dilute 3He–4He solid solutions with hcp structure

Contact Info

Product

Resources

About