Ceramic Superconductors Wiki

Yba 2 cu 3 o 7 x was the first ceramic superconductor discovered with t c greater than liquid nitrogen temperature.

Ceramic superconductors wiki.

Ceramics are normally insulators. A lanthanum barium copper and oxygen compound with a critical temperature of 30k. Any material exhibiting these properties is a superconductor unlike an ordinary metallic conductor whose resistance decreases gradually as its temperature is lowered even down to near absolute zero a superconductor has a. Chemical formula is yba2cu3o7.

X y means material x doped with element y t c is the highest reported transition temperature in kelvins and h c is a critical magnetic field in tesla. Because liquid nitrogen is relatively inexpensive and easier to handle there is a greater interest in the ceramic superconductor machines than the liquid helium cooled metal superconductor machines. This superconductor has a critical transition temperature around 90k well above liquid nitrogen s 77k. The superconductor we will be experimenting with is an yttrium y barium ba and copper cu composition.

A ceramic superconductor was discovered by alex müller and georg bednorz. The ceramic superconductors are also called high temperature or liquid nitrogen temperature superconductors. Tc is usually measured in degrees kelvin k 0 k being absolute zero the. Superconductivity is a set of physical properties observed in certain materials where electrical resistance vanishes and magnetic flux fields are expelled from the material.

Conductive ceramics conductive ceramics superconductors. Opened up the possibilities for new superconductors. The highest critical current density is achieved when x 0 so that the composition is yba 2 cu 3 o 7 but the material remains superconducting for values of x down to about 0 5. The temperature at which resistance ceases is referred to as the transition temperature or critical temperature tc.

Many ceramic superconductors physically behave as superconductors of the second type. Yttrium barium copper oxide ybco is a family of crystalline chemical compounds famous for displaying high temperature superconductivity it includes the first material ever discovered to become superconducting above the boiling point of liquid nitrogen 77 k at about 92 k many ybco compounds have the general formula y ba 2 cu 3 o 7 x also known as y123 although materials with other y. The yttrium compound is often called the 1 2 3 superconductor because of the ratios of its constituents. Superconductivity is the complete disappearance of electric resistance in materials that are cooled to extremely low temperatures.

The yttrium compound is somewhat unique in that it has a regular crystal structure while the lanthanum version is classified as a solid solution. Superconducting quantum interference device squid. Bcs means whether or not the superconductivity is explained within the bcs theory. The table below shows some of the parameters of common superconductors.