Abstract
Superstructures of oxycarbonate superconductor TlSr4-xBaxCu2(CO3)Oy (x=2; Tc=73K) were examined by electron diffraction and HRTEM techniques. Part of the crystals show a commensurate superstructure with a 6a0 periodicity due to crystallographic shears by c/2 to form -(C-C-C)-(Tl-Tl-Tl)-(C-C-C-)-(Tl-Tl-Tl)- type of sequences along the (100) direction in the basal planes. Incommensurate superstructures with longer periodicities up to 7.4a0 due to mixed intergrowths of -(C-C-C-C)- and -(C-C-C)- sequences were also observed. The average superstructure periodicity of the present specimen is around 7a0, which is relatively shorter than the value of 8a0 previously claimed by Goutenoire et al. [Physica C 210 (1993) 359] for a similar superconductor with Tc=62 K. This suggests the possibility of a close relationship between the modulation periodicity and the transition temperature in the TlSr4-xBaxCu2(CO3)Oy system with x=1-2.5. Observed structures were compared with an another type of superstructure recently discovered in HgBa2Sr2Cu2(CO3)Oy by Uehara et al.
| Original language | English |
|---|---|
| Pages (from-to) | 287-293 |
| Number of pages | 7 |
| Journal | Physica C: Superconductivity and its Applications |
| Volume | 217 |
| Issue number | 3-4 |
| DOIs | |
| Publication status | Published - Nov 20 1993 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Condensed Matter Physics
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Incommensurate and commensurate superstructures in the oxycarbonate superconductor TlSr4-xBaxCu2(CO3)Oy (x≈2). / Matsui, Y.; Ogawa, M.; Uehara, M.; Nakata, H.; Akimitsu, Jun.
In: Physica C: Superconductivity and its Applications, Vol. 217, No. 3-4, 20.11.1993, p. 287-293.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Incommensurate and commensurate superstructures in the oxycarbonate superconductor TlSr4-xBaxCu2(CO3)Oy (x≈2)
AU - Matsui, Y.
AU - Ogawa, M.
AU - Uehara, M.
AU - Nakata, H.
AU - Akimitsu, Jun
PY - 1993/11/20
Y1 - 1993/11/20
N2 - Superstructures of oxycarbonate superconductor TlSr4-xBaxCu2(CO3)Oy (x=2; Tc=73K) were examined by electron diffraction and HRTEM techniques. Part of the crystals show a commensurate superstructure with a 6a0 periodicity due to crystallographic shears by c/2 to form -(C-C-C)-(Tl-Tl-Tl)-(C-C-C-)-(Tl-Tl-Tl)- type of sequences along the (100) direction in the basal planes. Incommensurate superstructures with longer periodicities up to 7.4a0 due to mixed intergrowths of -(C-C-C-C)- and -(C-C-C)- sequences were also observed. The average superstructure periodicity of the present specimen is around 7a0, which is relatively shorter than the value of 8a0 previously claimed by Goutenoire et al. [Physica C 210 (1993) 359] for a similar superconductor with Tc=62 K. This suggests the possibility of a close relationship between the modulation periodicity and the transition temperature in the TlSr4-xBaxCu2(CO3)Oy system with x=1-2.5. Observed structures were compared with an another type of superstructure recently discovered in HgBa2Sr2Cu2(CO3)Oy by Uehara et al.
AB - Superstructures of oxycarbonate superconductor TlSr4-xBaxCu2(CO3)Oy (x=2; Tc=73K) were examined by electron diffraction and HRTEM techniques. Part of the crystals show a commensurate superstructure with a 6a0 periodicity due to crystallographic shears by c/2 to form -(C-C-C)-(Tl-Tl-Tl)-(C-C-C-)-(Tl-Tl-Tl)- type of sequences along the (100) direction in the basal planes. Incommensurate superstructures with longer periodicities up to 7.4a0 due to mixed intergrowths of -(C-C-C-C)- and -(C-C-C)- sequences were also observed. The average superstructure periodicity of the present specimen is around 7a0, which is relatively shorter than the value of 8a0 previously claimed by Goutenoire et al. [Physica C 210 (1993) 359] for a similar superconductor with Tc=62 K. This suggests the possibility of a close relationship between the modulation periodicity and the transition temperature in the TlSr4-xBaxCu2(CO3)Oy system with x=1-2.5. Observed structures were compared with an another type of superstructure recently discovered in HgBa2Sr2Cu2(CO3)Oy by Uehara et al.
UR - http://www.scopus.com/inward/record.url?scp=0027697747&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0027697747&partnerID=8YFLogxK
U2 - 10.1016/0921-4534(93)90331-J
DO - 10.1016/0921-4534(93)90331-J
M3 - Article
AN - SCOPUS:0027697747
VL - 217
SP - 287
EP - 293
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
SN - 0921-4534
IS - 3-4
ER -