Geodesic
Study of fine peculiarities of heat capacity in $\mathrm{YBa_2Cu_3O_y}$ films by means of the laser-coupled flat-coil-oscillator
Proceedings of the Yerevan State University. Physical and mathematical sciences, no. 1 (2011), pp. 49-54.

Voir la notice de l'article provenant de la source Math-Net.Ru

Improvements in the "hybrid” imaging method, based on traditional Laser Scanning Microscopy in combination with the single-layer flat-coil-oscillator (SFCO) sensitive technique introduced by authors earlier, are discussed. This method is capable of imaging $\mathrm{2D}$-grained structure, as well as the normal-tosuperconductive phase transition in flat thin high-$T_c$ superconductive materials with $1–2 \mu m$ spatial resolution. It enabled to detect weakly expressed peculiarities of the heat capacity in $\mathrm{YBa_2Cu_3O_y}$ film (preceding the well-known specific heat "jump”), which are important for true understanding of the real nature of superconductivity phenomenon. The method uses a well-focused $\mathrm{He-Ne}$ laser beam as a probing signal, and the SFCO-technique as a high-resolution sensing tool.
Keywords: Cryogenic laser scanning microscope (CLSM), heat capacity of $\mathrm{YBa_2Cu_3O_y}$ film, high-$T_c$ superconductive (HTS) $\&$ low-$T_c$ superconductive (LTS) materials, normal-to-superconductive (N/S) phase transition, single-layer flat-coil-oscillator test-method (SFCO-technique).
Mots-clés : imaging technique 
@article{UZERU_2011_1_a8,
     author = {S. G. Gevorgyan and G. H. Karapetyan and H. G. Shirinyan and S. T. Muradyan and G. S. Gevorgyan and B. K. Kurghinyan and V. S. Gevorgyan and A. A. Polyanskii},
     title = {Study of fine peculiarities of heat capacity in  $\mathrm{YBa_2Cu_3O_y}$ films by means of the laser-coupled flat-coil-oscillator},
     journal = {Proceedings of the Yerevan State University. Physical and mathematical sciences},
     pages = {49--54},
     publisher = {mathdoc},
     number = {1},
     year = {2011},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/UZERU_2011_1_a8/}
}
TY  - JOUR
AU  - S. G. Gevorgyan
AU  - G. H. Karapetyan
AU  - H. G. Shirinyan
AU  - S. T. Muradyan
AU  - G. S. Gevorgyan
AU  - B. K. Kurghinyan
AU  - V. S. Gevorgyan
AU  - A. A. Polyanskii
TI  - Study of fine peculiarities of heat capacity in  $\mathrm{YBa_2Cu_3O_y}$ films by means of the laser-coupled flat-coil-oscillator
JO  - Proceedings of the Yerevan State University. Physical and mathematical sciences
PY  - 2011
SP  - 49
EP  - 54
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/UZERU_2011_1_a8/
LA  - en
ID  - UZERU_2011_1_a8
ER  - 
%0 Journal Article
%A S. G. Gevorgyan
%A G. H. Karapetyan
%A H. G. Shirinyan
%A S. T. Muradyan
%A G. S. Gevorgyan
%A B. K. Kurghinyan
%A V. S. Gevorgyan
%A A. A. Polyanskii
%T Study of fine peculiarities of heat capacity in  $\mathrm{YBa_2Cu_3O_y}$ films by means of the laser-coupled flat-coil-oscillator
%J Proceedings of the Yerevan State University. Physical and mathematical sciences
%D 2011
%P 49-54
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/UZERU_2011_1_a8/
%G en
%F UZERU_2011_1_a8
S. G. Gevorgyan; G. H. Karapetyan; H. G. Shirinyan; S. T. Muradyan; G. S. Gevorgyan; B. K. Kurghinyan; V. S. Gevorgyan; A. A. Polyanskii. Study of fine peculiarities of heat capacity in  $\mathrm{YBa_2Cu_3O_y}$ films by means of the laser-coupled flat-coil-oscillator. Proceedings of the Yerevan State University. Physical and mathematical sciences, no. 1 (2011), pp. 49-54. http://geodesic.mathdoc.fr/item/UZERU_2011_1_a8/

[1] J.G. Bednorz, K.A. Müller, “Possible high $T_c$ superconductivity in the $\mathrm{Ba}$-$\mathrm{La}$-$\mathrm{Cu}$-$\mathrm{O}$ system”, Z. Phyzik B, 64 (1986), 189–193

[2] A. Mourachkine, “Principles of Superconductivity”, Room-temperature Superconductivity, chapter 4 , arXiv:cond-mat/0409240, Cambridge Internat. Sci. Publ., Cambridge, 2004

[3] S.G. Gevorgyan, Ph.D. Thesis, Detection of ionizing radiation by the superheated superconducting grains, Institute for Physical Researches, National Academy of Sciences. Armenia, 1989

[4] S.G. Gevorgyan, T. Kiss, T. Ohyama, M. Inoue, A.A. Movsisyan, H.G. Shirinyan, V.S. Gevorgyan, T. Matsushita, M. Takeo, “New paramagnetic peculiarity of the superconductive transition detected by a highly sensitive OFC magnetometer”, Superconductor Science and Technology, 14:12 (2001), 1009–1013

[5] W.S. Corak, C.B. Satterthwaite, Phys. Rev., 99 (1954), 1660

[6] S. Gevorgyan, H. Shirinyan, A. Manukyan, E. Sharoyan, M. Takeo, A. Polyanskii, A. Sarkisyan, T. Matsushita, “Flat coil-based tunnel diode oscillator enabling to detect the real shape of the superconductive transition curve and capable of imaging the properties of HTSC films with high spatial resolution”, Nucl. Instr. Meth. Phys. Res. A, 520:1–3 (2004), 314–319

[7] S.G. Gevorgyan, T. Kiss, A.A. Movsisyan, H.G. Shirinyan, Y. Hanayama, H. Katsube, T. Ohyama, M. Takeo, T. Matsushita, K. Funaki, “Highly sensitive open-flat coil magnetometer for the $\lambda (H,T)$ measurements in plate-like high-$T_c$ cuprates”, Review of Scientific Instruments, 71:3 (2000), 1488–1494

[8] S.G. Gevorgyan, T. Kiss, T. Ohyama, A. Movsisyan, H. Shirinyan, V.S. Gevorgyan, T. Matsushita, M. Takeo, K. Funaki, “Calibration of the open-flat coil-based tunnel diode oscillator technique (OFC magnetometer) for quantitative extraction of physical characteristics of superconductive state”, Physica C: Supercond. $\$ Appl., 366:1 (2001), 6–12

[9] S.G. Gevorgyan, T. Kiss, H.G. Shirinyan, A.A. Movsisyan, T. Ohyama, M. Inoue, T. Matsushita, M. Takeo, “The possibility of detection of small absorption in $\mathrm{HTS}$ thin films by means of the highly sensitive OFC magnetometer”, Physica C: Supercond. $\$ Appl., 363:2 (2001), 113–118

[10] H.G. Shirinyan, “Sensitive thermosensor for cryogenic applications working in a wide temperature range”, J. of Contemporary Physics (NAS of Armenia), 37 (2002), 387–390

[11] S.G. Gevorgyan, H.G. Shirinyan, G.H. Karapetyan, G.S. Gevorgyan, A.A. Polyanskii, “Imaging of the grain structure of thin HTS film by a single-layer flat-coil-oscillator test-method ”, Proceedings of the YSU. Physical $\$ Mathematical Sciences, 2009, no. 2, 50–54

[12] V.F. Gantmakher, N.I. Golovko, I.G. Naumenko, A.M. Neminsky, A.V. Petinova, “Temperature dependence of the magnetic field penetration depth in $\mathrm{YBa_2Cu_3O_{7-\delta}}$ measured on ultra fine powder”, Physica C: Supercond. $\$ Appl., 171 (1990), 223–230

[13] B.K. Kurghinyan, S.G. Gevorgyan, V.R. Ohanyan, “Weakly expressed peculiarities of specific heat of superconductive materials and their relation to paramagnetic effect, detected by SFCO method”, Uchenye zapiski EGU (Proceedings of the YSU), 2008, no. 3, 82–90 (in Armenian)