Second-Sound Waves in Cryocrystals

The self-coordinated values of parameters of cryocrystals of orthodeuterium, parahydrogen, and neon (temperature, isotope concentrations, and the sizes of samples), which define the range of second-sound waves existence, are found. The limiting isotope concentrations, below which the propagation of...

Повний опис

Збережено в:
Бібліографічні деталі
Опубліковано в: :Український фізичний журнал
Дата:2010
Автори: Khodusov, V.D., Blinkina, A.A.
Формат: Стаття
Мова:Англійська
Опубліковано: Відділення фізики і астрономії НАН України 2010
Теми:
Онлайн доступ:https://nasplib.isofts.kiev.ua/handle/123456789/56196
Теги: Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
Назва журналу:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Цитувати:Second-Sound Waves in Cryocrystals / V.D. Khodusov, A.A. Blinkina // Український фізичний журнал. — 2010. — Т. 55, № 5. — С. 543-546. — Бібліогр.: 12 назв. — англ.

Репозитарії

Digital Library of Periodicals of National Academy of Sciences of Ukraine
_version_ 1860209621304606720
author Khodusov, V.D.
Blinkina, A.A.
author_facet Khodusov, V.D.
Blinkina, A.A.
citation_txt Second-Sound Waves in Cryocrystals / V.D. Khodusov, A.A. Blinkina // Український фізичний журнал. — 2010. — Т. 55, № 5. — С. 543-546. — Бібліогр.: 12 назв. — англ.
collection DSpace DC
container_title Український фізичний журнал
description The self-coordinated values of parameters of cryocrystals of orthodeuterium, parahydrogen, and neon (temperature, isotope concentrations, and the sizes of samples), which define the range of second-sound waves existence, are found. The limiting isotope concentrations, below which the propagation of second-sound waves is possible, are established. The sizes of samples, starting from which their increase does not essentially influence the damping of second-sound waves are found. The results are presented in threedimensional plots. Знайдено узгодженi значення параметрiв крiокристалiв ортодейтерiю, параводню та неону (температури, концентрацiї iзотопiв, домiшок та розмiрiв зразкiв), що визначають область iснування хвиль другого звуку. Встановлено граничнi концентрацiї iзотопiв, нижче за якi можливе поширення хвиль другого звуку, а також визначено розмiри зразкiв, починаючи з яких їх збiльшення не впливає на загасання хвиль другого звуку. Результати наведено у виглядi тривимiрних графiкiв.
first_indexed 2025-12-07T18:13:43Z
format Article
fulltext SECOND-SOUND WAVES IN CRYOCRYSTALS SECOND-SOUND WAVES IN CRYOCRYSTALS V.D. KHODUSOV, A.A. BLINKINA Karazin Kharkiv National University (4, Svobody Sq., Kharkiv 61077, Ukraine; e-mail: blinkina@ gmail. com,vkhodusov@ ukr. net ) PACS 66.70.-f, 61.72.S c©2010 The self-coordinated values of parameters of cryocrystals of orth- odeuterium, parahydrogen, and neon (temperature, isotope con- centrations, and the sizes of samples), which define the range of second-sound waves existence, are found. The limiting isotope con- centrations, below which the propagation of second-sound waves is possible, are established. The sizes of samples, starting from which their increase does not essentially influence the damping of second-sound waves are found. The results are presented in three- dimensional plots. 1. Introduction For the first time, second-sound waves (SSW) in solid bodies were observed experimentally in 4He cryocrystals [1]. The question on an opportunity of the SSW propa- gation in other cryocrystals was discussed in a number of works [2–5]. For the experimental detection of SSW, it is necessary to know the compatible areas of values for the most essential parameters such as the tempera- ture, impurity and isotope concentrations, and sizes of samples. This compatibility of parameters can be ob- tained (if the second sound damping factor is known) from a condition of weakness of the damping of these waves. It is possible to write down the damping coef- ficient using the diffusion times for various dissipative processes running in a phonon gas [6] which are caused by umklapp processes, scattering on impurities and iso- topes, and scattering on the sample boundaries. The direct calculation of these times is rather difficult. It is known that the SSW propagation is possible in a vicin- ity of the maximum of the thermal conductivity coeffi- cient of a cryocrystal. According to this, it is possible to use phenomenological values of collision frequencies connected with these times which are used in the Call- away model to describe experimentally observable de- pendences of the thermal conductivity coefficient on the temperature in a low-temperature range. The main contribution to the SSW damping factor is given by the phonon scattering on impurities and iso- topes and by the scattering on the sample boundaries. In case of orthodeuterium (o−D2), parahydrogen (p−H2), and neon (Ne) cryocrystals, it is possible to produce pure enough samples, in which the role of impurities will be insignificant; however, there remains an essential role of isotopes. It is necessary to consider the phonon scatter- ing on boundaries in an absolutely different way. SSW propagate in crystals in the phonon gas, when the hy- drodynamic regime in it is realized due to the fast nor- mal processes of phonon interaction. In this case, before reaching the boundary, a phonon will experience a set of normal collisions. Therefore, the free path will increase due to the boundary scattering, and the contribution of these processes to the damping coefficient will decrease. In the present work, we determined the coordinated areas of concentrations of hydrogen and 22Ne isotope, sizes of samples, and temperatures, where SSW exist. The obtained results can be used for carrying out the experiments on the SSW registration in orthodeuterium, parahydrogen, and neon. 2. Existence of Second-Sound Waves in Solid Bodies In work [6], the general theory of secondary waves in a gas of Bose quasiparticles which are, in particular, second-sound waves in a phonon gas has been con- structed for solid bodies. Meanwhile, the description of SSW was established in the reduced isotropic crystal model, by using the modulus of elasticity. The SSW dis- persion equation has been found in the same work [6] and has the following form: Ω ( Ω2 −W 2 IIk̃ 2 ) − 2iW 2 IIk̃ 2ΓII = 0. (1) Here, WII is the SSW phase velocity in an isotropic phonon gas, and ΓII is the SSW damping factor. The expressions for WII and ΓII are as follows [6]: WII = ( TS2/Cρ̃ ) , ΓII = r 2ρ̃ + [ 1 2ρ̃ ( 4 3 η̃ + ζ̃ ) + 1 2C κ̃ ] k2, (2) where ρ̃ – phonon density, r – coefficient of external fric- tion caused by the phonon interaction without the quasi- momentum conservation (umklapp processes, scattering ISSN 2071-0194. Ukr. J. Phys. 2010. Vol. 55, No. 5 543 V.D. KHODUSOV, A.A. BLINKINA on impurities, isotopes, and boundaries of the sample), η̃ and ζ̃ – coefficients of first and second viscosities, re- spectively„ and κ̃ – coefficient of hydrodynamical ther- mal conductivity. For a phonon gas in the low-temperature range ΘD/T�1 in the reduced isotropic crystal model, the following expressions for the densities of thermal ca- pacity and entropy, phonon density, Debye tempera- ture, and average sound velocity are obtained: C = 3S = 2π2 15 k4 BT 3 ~3V 3 t ( 2 + β3 ) , ρ̃ = 2π2 45 k4 BT 4 ~3V 5 t ( 2 + β5 ) , ΘD = 2π~Vs/kBa, VS = Vt ( 3 2+β3 )1/3 , where Vl, Vt – veloci- ties of longitudinal and transversal sounds, β = Vt/Vl, kB – Boltzmann constant, and a – lattice parameter. The second sound velocity WII = V 2 t 3 ( 2 + β3 2 + β5 ) . (3) We now introduce the diffusion times by the relations τη̃ = η̃ ρ̃W 2 II ; τζ̃ = ζ̃ ρ̃W 2 II ; τκ̃ = κ̃ CW 2 II ; τR = ρ̃ r (4) and the notation τN = 4 3 τη̃ + τζ̃ + τκ̃. (5) Then the introduction of the collision frequencies νi connected with the diffusion times τi by the relation νi = 1/τi allows us to write ΓII in the form ΓII = 1 2 [ νR + 1 νN Ω2 ] . (6) The condition of existence of a weakly decaying SSW is ΓII � Ω, which leads to a condition imposed on the fre- quency Ω known as a “window” of SSW existence. The given condition is written down in a general form. There- fore, for a more detailed study of the range of SSW exis- tence and for finding the coordinated boundary values of parameters, at which the existence of a weakly decaying SSW is possible, it is necessary to specify it. We demand the next condition to be satisfied: ΓII ≤ 10Ω. (7) This leads to the following frequency “window” of SSW existence: 0.1νN − √ ν2 N 102 − νNνR ≤ ΩII ≤ 0.1νN+ √ ν2 N 102 − νNνR. (8) Equation (8) yields the desired relation between the pa- rameters νN ≥ 100νR. (9) 3. Definition of the Coordinated Values of Parameters, at Which SSW Exist in Cryocrystals The expression for the scattering frequency due to resis- tive processes is as follows: νR = νiso + νBeff + νU. (10) Here, νiso – frequency of phonon scattering on isotopes, νBeff – frequency of scattering on boundaries of a sample, νU – scattering frequency due to umklapp processes. The collision frequency on isotopes is taken into ac- count for all crystals with the use of the formula [7,8] νiso (x) = a3 4πV 3 S ( ΔM M )2 x4T 4Cd, (11) where Cd = Nd/N – concentration of isotopes, ΔM – a difference between nuclear weights of isotopes and that of the basic substance, M – weight of basic atoms, and x – dimensionless variable. We considered the phonon scattering on boundaries which depends on a relation between the free path length of phonons due to normal processes lN = τNVS and that in the sample bulk D. SSW exist in dielectrics if the hydrodynamical mode in the description of phonons is realized. Thus, the inequality lN � D is valid. Phonons that are in the sample bulk will experience a set of nor- mal collisions before reaching the boundary. As a re- sult, the way which is passed between two collisions with boundaries essentially increases. Using the known for- mulas for the Brown movement, it is easy to show that the trajectory between two collisions with a boundary will be of the order of D2/lN [9]. This implies that the effective frequency of phonon collisions with the bound- ary is νBeff = V 2 S D2νN . (12) For the numerical estimations and the calculations of conditions for the existence of weakly decaying SSW in cryocrystalls of orthodeuterium and parahydrogen and in crystals of neon, we used data given in works [3,4,10,11] and presented in a tabular form in work [12]. We give here only Table for the averaged frequencies of phonon collisions. 544 ISSN 2071-0194. Ukr. J. Phys. 2010. Vol. 55, No. 5 SECOND-SOUND WAVES IN CRYOCRYSTALS Expressions for the average collision frequencies in the Callaway model for various crystals Crystal o−D2 p−H2 Ne νN , s−1 1.4× 106T 5 1.9× 106T 5 1.3× 107T 4 νU, s−1 1.3× 109T 3e [ −37 T ] 1.4× 109T 3e [ −40 T ] 4× 106T 5e [ −13 T ] νiso, s−1 1.3× 109T 4Cd 2.3× 108T 4Cd 9.5× 107T 4Cd νBeff , s−1 9× 103T−5/D2 4.3× 103T−5/D2 0.2× 103T−4/D2. Fig. 1. Range of the self-coordinated parameters for crystals of orthodeuterium Using these average values of frequencies of phonon collisions and inequality (9), we build the plots of self- coordinated values of the parameters (T,Cd, D) deter- mining the range of SSW existence in the considered cryocrystals. These plots are presented in Figs. 1–3. 4. Conclusions The values of parameters lying on surfaces are limitind values of the self-coordinated parameters, at which the SSW propagation is possible. The range below these sur- faces corresponds to the SSW existence in cryocrystals. Fig. 2. Range of the self-coordinated parameters for crystals of parahydrogen The analysis of the resulted plots enables us to estab- lish the limiting values of isotope concentrations, below which the SSW propagation is possible. For orthodeu- terium, parahydrogen, and neon, Cdlim are, respectively, 3.1 × 10−5, 2.7 × 10−4, and 1.3 × 10−3. In addition, it is seen from plots that, starting from the sizes of the order of 0.5 cm, an increase in the sample size weakly influences the range, where SSW exist. Choosing the certain parameters in the range of SSW existence from inequality (8), it is possible to find a fre- quency spectrum of weakly decaying SSW. For example, ISSN 2071-0194. Ukr. J. Phys. 2010. Vol. 55, No. 5 545 V.D. KHODUSOV, A.A. BLINKINA Fig. 3. Range of the self-coordinated parameters for crystals of neon let us consider parahydrogen: if we take a crystal with D = 0.7 cm, the isotope concentration Cd = 3× 10−5 at T = 2 K, the frequency range is 0 ≤ ΩII ≤ 4.9×106 s−1. The knowledge of this spectrum is very essential for at- tempts to register SSW in experiments on the observa- tion of the thermal pulse evolution. 1. C.C. Ackerman and W.C. Overton, Phys. Rev. Letters. 22, 764 (1969). 2. N.N. Zholonko, B.Ya. Gorodilov, and A.I. Krivchikov, JETP Lett. 55, 167 (1992). 3. R.M. Kimber and S.J. Rogers, J. Phys. C: Solid State Phys. 6, 2279 (1973). 4. O.A. Koroluk, B.Ya. Gorodilov, A.I. Krivchikov, and V.V. Dudkin, Fiz. Nizk. Temp. 26, 323 (2000). 5. T.N. Antsigina, B.Ya. Gorodilov, N.N. Zholonko, A.I. Krivchikov, V.G. Manzhelii, and V.A. Slusarev, Fiz. Nizk. Temp. 18, 417 (1992). 6. A.I. Akhiezer, V.F. Aleksin, and V.D. Khodusov, Low Temp. Phys. 20, 939 (1994); Low Temp. Phys. 21, 1 (1995). 7. R. Berman, Thermal Conductivity in Solids (Oxford Uni- versity Press, Oxford, 1976). 8. A.P. Zhernov and A.V. Inyushkin, Uspekhi. Fiz. Nauk 45, 573 (2002). 9. R.N. Gurzhi, Uspekhi. Fiz. Nauk 94, 689 (1968). 10. Properties of the Condensed Phases of Hydrogen and Oxygen (Reference Book) (Naukova Dumka, Kiev, 1984). 11. M. M. Tarasenko and V.A. Bezuglyi, Thermophysical Properties of Substances and Materials (Standards Publ. House, Moscow, 1976). 12. V.D. Khodusov and A.A. Blinkina, Fiz. Nizk. Temp. 35, 451 (2009). Received 22.12.09 ХВИЛI ДРУГОГО ЗВУКУ У КРIОКРИСТАЛАХ В.Д. Ходусов, А.А. Блiнкiна Р е з ю м е Знайдено узгодженi значення параметрiв крiокристалiв орто- дейтерiю, параводню та неону (температури, концентрацiї iзо- топiв, домiшок та розмiрiв зразкiв), що визначають область iснування хвиль другого звуку. Встановлено граничнi концен- трацiї iзотопiв, нижче за якi можливе поширення хвиль друго- го звуку, а також визначено розмiри зразкiв, починаючи з яких їх збiльшення не впливає на загасання хвиль другого звуку. Ре- зультати наведено у виглядi тривимiрних графiкiв. 546 ISSN 2071-0194. Ukr. J. Phys. 2010. Vol. 55, No. 5
id nasplib_isofts_kiev_ua-123456789-56196
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
issn 2071-0194
language English
last_indexed 2025-12-07T18:13:43Z
publishDate 2010
publisher Відділення фізики і астрономії НАН України
record_format dspace
spelling Khodusov, V.D.
Blinkina, A.A.
2014-02-13T20:18:00Z
2014-02-13T20:18:00Z
2010
Second-Sound Waves in Cryocrystals / V.D. Khodusov, A.A. Blinkina // Український фізичний журнал. — 2010. — Т. 55, № 5. — С. 543-546. — Бібліогр.: 12 назв. — англ.
2071-0194
PACS 66.70.-f, 61.72.S
https://nasplib.isofts.kiev.ua/handle/123456789/56196
The self-coordinated values of parameters of cryocrystals of orthodeuterium, parahydrogen, and neon (temperature, isotope concentrations, and the sizes of samples), which define the range of second-sound waves existence, are found. The limiting isotope concentrations, below which the propagation of second-sound waves is possible, are established. The sizes of samples, starting from which their increase does not essentially influence the damping of second-sound waves are found. The results are presented in threedimensional plots.
Знайдено узгодженi значення параметрiв крiокристалiв ортодейтерiю, параводню та неону (температури, концентрацiї iзотопiв, домiшок та розмiрiв зразкiв), що визначають область iснування хвиль другого звуку. Встановлено граничнi концентрацiї iзотопiв, нижче за якi можливе поширення хвиль другого звуку, а також визначено розмiри зразкiв, починаючи з яких їх збiльшення не впливає на загасання хвиль другого звуку. Результати наведено у виглядi тривимiрних графiкiв.
en
Відділення фізики і астрономії НАН України
Український фізичний журнал
Тверде тіло
Second-Sound Waves in Cryocrystals
Хвилі другого звуку у кріокристалах
Article
published earlier
spellingShingle Second-Sound Waves in Cryocrystals
Khodusov, V.D.
Blinkina, A.A.
Тверде тіло
title Second-Sound Waves in Cryocrystals
title_alt Хвилі другого звуку у кріокристалах
title_full Second-Sound Waves in Cryocrystals
title_fullStr Second-Sound Waves in Cryocrystals
title_full_unstemmed Second-Sound Waves in Cryocrystals
title_short Second-Sound Waves in Cryocrystals
title_sort second-sound waves in cryocrystals
topic Тверде тіло
topic_facet Тверде тіло
url https://nasplib.isofts.kiev.ua/handle/123456789/56196
work_keys_str_mv AT khodusovvd secondsoundwavesincryocrystals
AT blinkinaaa secondsoundwavesincryocrystals
AT khodusovvd hvilídrugogozvukuukríokristalah
AT blinkinaaa hvilídrugogozvukuukríokristalah