Lanthanum barium copper oxide, or LBCO, is an inorganic compound with the formula CuBa_0.15La_1.85O₄. It is a black solid produced by heating an intimate mixture of

barium oxide Barium oxide, also known as baria, is a white hygroscopic non-flammable compound with the formula BaO. It has a cubic structure and is used in cathode ray tubes, crown glass, and catalysts. It is harmful to human skin and if swallowed in larg ...

copper(II) oxide Copper(II) oxide or cupric oxide is an inorganic compound with the formula CuO. A black solid, it is one of the two stable oxides of copper, the other being Cu2O or copper(I) oxide (cuprous oxide). As a mineral, it is known as tenorite. It is ...

, and

lanthanum oxide Lanthanum(III) oxide, also known as lanthana, chemical formula , is an inorganic compound containing the rare earth element lanthanum and oxygen. It is used in some ferroelectric materials, as a component of optical materials, and is a feedstock ...

in the presence of

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...

. The material was discovered in 1986 and was the first

high temperature superconductor High-temperature superconductors (abbreviated high-c or HTS) are defined as materials that behave as superconductors at temperatures above , the boiling point of liquid nitrogen. The adjective "high temperature" is only in respect to previ ...

. Johannes Georg Bednorz and K. Alex Müller shared the 1987

Nobel Prize The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...

for the discovery that this material exhibits superconductivity at the then unusually high temperature. This finding led to intense and fruitful efforts to generate other

cuprate superconductor Cuprate superconductors are a family of high-temperature superconducting materials made of layers of copper oxides (CuO2) alternating with layers of other metal oxides, which act as charge reservoirs. At ambient pressure, cuprate superconductor ...

s. Lanthanum barium copper oxide is related to the far simpler compound lanthanum cuprate, which has a similar structure. In lanthanum barium copper oxide, some of the La(III) centers are replaced by Ba(II), which has a similar ionic radius. This Ba-for-La replacement causes removal of some electrons from the d-band associated with the sheets of copper oxide.

References

High-temperature superconductors Lanthanum compounds Barium compounds Copper compounds Oxides {{CMP-stub