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NIST High Temp. Superconducting Materials (HTS) Database:

NIST Standard Reference Database 62

Last Update to Data Content: 1996

DOI: https://doi.org/10.18434/T4KP8J

Bibliographic Information

Title: Hall Effect Measurements on YBa2Cu4O8 Single Crystals
Author(s): J. Lohle, J. Karpinski, H. Schwer, and P. Wachter
Publication: Physica C Volume: 258 Issue: Not Available Year: 1996 Page(s): 279-283
Editor(s): Not Available
Publisher: Elsevier Science Publishers B.V.
Language: English
Notes: Not Available
Keywords: Material Specification, Hall Coefficient

Materials and Properties

Y:124; [Y-Ba-Cu-O]
Material Specification for Y:124; [Y-Ba-Cu-O] Process: Crystal Growth
Notes: The authors cite J. Karpinski et al., J. Less-Common Metals, Vol. 164-165, 3 (1990), and summarize the procedure as follows. "Single crystals of YBa2Cu4O8 were grown by a high-pressure synthesis technique... The crystals selected for the measurements were thin rectangular plates, where the principal axes a, b and c were oriented along the edges. Typical dimensions along the a- and b-axes were 300-400 µm. The c-axis dimension was between 10 µm and 20 µm."
Formula: YBa2Cu4O8
Informal Name: Y:124
Chemical Family: Y-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Single Crystal
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:

Hall Coefficient for Y:124; [Y-Ba-Cu-O]
Direction of Current () Temperature (K) Hall Coefficient (mm3 /C)
a-axis 51 0.000
a-axis 55 -0.035
a-axis 57 -0.056
a-axis 58 0.096
a-axis 60 0.32
a-axis 64 0.55
a-axis 67 0.68
a-axis 69 0.63
a-axis 74 0.45
a-axis 80 0.37
a-axis 90 0.29
a-axis 100 0.26
a-axis 110 0.22
a-axis 120 0.19
a-axis 130 0.19
a-axis 150 0.16
a-axis 160 0.15
a-axis 170 0.15
a-axis 180 0.15
a-axis 190 0.13
a-axis 200 0.14
a-axis 210 0.13
a-axis 220 0.12
a-axis 230 0.11
a-axis 240 0.12
a-axis 250 0.10
a-axis 260 0.09
a-axis 270 0.09
a-axis 280 0.08
b-axis 50 -0.02
b-axis 56 0.03
b-axis 61 0.37
b-axis 61 0.81
b-axis 66 1.02
b-axis 66 1.07
b-axis 71 0.91
b-axis 71 0.63
b-axis 76 0.45
b-axis 96 0.29
b-axis 124 0.21
b-axis 157 0.13
b-axis 188 0.16
b-axis 224 0.13
b-axis 252 0.11
b-axis 269 0.11
b-axis 277 0.08
b-axis 290 0.08
Measurement Method: Four-point Hall method
"For the Hall effect measuremnts we made the classical geometrical arrangement of the electrical contacts. ... For measuring the Hall effect in the b-direction, current contacts, which nearly covered the whole ac-planes, are attached, forcing a homogeneous current distribution. Voltage contacts are mounted at the center of the bc-planes over the whole thickness of the crystal. ... Gold pads were evaporated through a mask produced by a photolithographic technique at the edges of the crystals. After annealing at 500 °C, gold wires were attached by gold epoxy. The resulting contact resistivity was less than 1 Ω. The measurements were carried out by a standard four-point low-frequency ac (33 Hz) method. For each measurement point the crystal was rotated by 180°, so that the small unbalanced resistivity signal could be subtracted."

Cautions: Evaluated Data
"A further investigation with a Burger precession X-ray single-crystal camera showed that the crystals with a nearly temperature-independent Hall coefficients are not really single crystals. These samples consisted of two single crystals with parallel c-axes but with ab-planes twisted... The Hall coefficient decreased with increasing temperature, as is typical in high-temperature superconductors. For temperatures below Tc the curves are different. In this temperature range... it is important to note that this is the Hall coefficient in a magnetic field of 4 T." Digitized data were obtained from Figure 6 of the paper.