A Data Sets

 

Superconductivity homepage UBC Superconductivity
Data Sets		 UBC Crest
A number of our experimental results on high temperature superconductors are presented here and are available for viewing or downloading to your own computer. We ask that the figures not be reproduced in a publication without our permission. The data sets are all either in or submitted to paper journals, so we consider them to be in the public domain. However, if you intend to make use of the data in one of your own publications, we would like to hear from you. We can supply you with further details and the appropriate references. Since this is a somewhat novel approach to getting experimental information to interested researchers, we would appreciate any comments or feedback that you might have. Please direct any correspondence to bonn "at" physics.ubc.ca.

MICROWAVE PENETRATION DEPTH MEASUREMENTS AT 1 GHz

All data files present lambda(T) with the temperature in Kelvin in column 1 and the penetration depth in Angstroms in column 2. The data are a combination of the temperature dependence measured by microwave techniques (Kamal, Bonn, Liang, and Hardy) and the value of lambda(T=0) inferred from the far infrared measurements of T. Timusk, C. Homes, D. Basov and coworkers. There are many ways to plot this information; the standard plots of penetration depth and the normalized superfluid fraction can be seen by clicking on Bonn et al., Czech. J. Phys. 46, 3195 (1996). An alternative presentation is shown below, along with links to the data files.

The penetration depth can be used to directly extract the superfluid density over the effective mass (or the superfluid stiffness if you like). The figures below are presented as a number of holes per unit cell per copper oxygen plane, divided by the effective mass ratio.

CLICK ON A FIGURE IF YOU WISH TO ACCESS A FULL SIZE POSTSCRIPT IMAGE
CLICK ON A DATASET TO THE RIGHT IF YOU WANT TO DOWNLOAD THE ACTUAL NUMBERS

Superfluid density in the a-direction

Superfluid density in the a-direction

(in the plane, perpendicular to the chains)

DATA SETS

a-axis of YBa2Cu3O6.60
a-axis of YBa2Cu3O6.95
a-axis of YBa2Cu3O6.99
Superfluid density in the b-direction

Superfluid density in the b-direction

(in the chain direction)

DATA SETS

b-axis of YBa2Cu3O6.60
b-axis of YBa2Cu3O6.95
b-axis of YBa2Cu3O6.99
Superfluid density in the c-direction

Superfluid density in the c-direction

(perpendicular to the planes)

DATA SETS

c-axis of YBa2Cu3O6.60
c-axis of YBa2Cu3O6.95
c-axis of YBa2Cu3O6.99

MICROWAVE SURFACE RESISTANCE IN THE a-DIRECTION, YBa2Cu3O6.993

The figures below are from an article that compiles measurements at 5 different microwave frequencies, all performed on the same sample of ultra-high purity overdoped YBCO (Hosseini et al., Phys. Rev. B). This provides the most complete set yet for generating the conductivity spectrum at microwave frequencies. Beside the figures, you can click to download either the raw surface resistance measurements or the conductivities derived from them.

Rs in the a-direction

Microwave surface resistance in the a-direction

(in the plane, perpendicular to the chains)
of an ultra-high purity crystal of YBa2Cu3O6.993

DATA SETS

1 GHz
2 GHz
13 GHz
22 GHz
75 GHz
Conductivity in the a-direction

Microwave conductivity in the a-direction

(in the plane, perpendicular to the chains)
of an ultra-high purity crystal of YBa2Cu3O6.993

DATA SETS

1 GHz
2 GHz
13 GHz
22 GHz
75 GHz

MICROWAVE SURFACE RESISTANCE IN THE b-DIRECTION, YBa2Cu3O6.993

The figures and data below are from an article on the b-axis electrodynamics of the same crystal as the above a-axis data, at the same 5 frequencies (and same doping) (Harris et al., Phys. Rev. B). Some conductivity numbers are not provided because their calculation requires both the real and imaginary parts of the surface impedance for accurate results, and three of the resonators used are unable to provide the latter. While the conductivity graph should be an excellent approximation to the truth, we cannot be certain of that at all frequencies.

Rs in the b-direction
PostScript  |  GIF (768×614)

Microwave surface resistance in the b-direction

(in the plane, parallel to the chains)
of an ultra-high purity crystal of YBa2Cu3O6.993
First column: Temperature in Kelvins.
Second column: Rs in Ohms.

DATA SETS

1 GHz
2 GHz
13 GHz
22 GHz
75 GHz
Conductivity in the b-direction
PostScript  |  GIF (786×612)

Microwave conductivity in the b-direction

(in the plane, parallel to the chains)
of an ultra-high purity crystal of YBa2Cu3O6.993
First column: temperature in Kelvins.
Second column: sigma1 in Ohm-1m-1.

DATA SETS

1 GHz
22 GHz
For the reasons described above, we have elected to
release the remaining three files by request only.

BROADBAND MEASUREMENTS ON ORTHO-II YBa2Cu3O6.50

These data files contain the real parts of the surface resistance and conductivity of an Ortho-II single crystal, in the a direction, at four temperatures. The approximations used to extract the conductivity should be valid for the frequency range and temperatures encountered. The format used in the data files is:
Frequency (Hz) Rs (Ohms) sigma1 (Ohm-1m-1)

Graph
PostScript  |  GIF image (759×776)

Microwave surface resistance and
conductivity in the a-direction

(in the plane, perpendicular to the chains)
of an ultra-high purity crystal of Ortho-II YBa2Cu3O6.50

DATA SETS

1.3 K
2.7 K
4.3 K
6.7 K
Superconductivity homepage UBC Physics and Astronomy homepage