Substances that undergo superconducting phenomena are called superconductors. Relevant knowledge is as follows:
1. Superconductivity refers to the phenomenon that the resistance of certain materials suddenly disappears under low temperature conditions, and there is no energy loss at all when current passes through. This phenomenon was first discovered by Dutch physicist Heike Camerin Oness in 1911.
2. Superconductors have extremely strong electrical conductivity and can conduct current without resistance. Therefore, they are widely used in energy, electronics, medical and other fields. For example, superconducting cables can greatly reduce energy loss during power transmission; superconducting magnets can be used in medical equipment such as MRI.
3. Superconductors are divided into two categories: high-temperature superconductors and low-temperature superconductors. The critical temperature of high-temperature superconductors is relatively high, generally above the temperature of liquid nitrogen (77K), which allows them to exhibit superconducting properties at room temperature. Low-temperature superconductors have a lower critical temperature and need to be cooled to close to absolute zero (0K) to exhibit superconducting properties.
4. The currently known high-temperature superconductors are mainly iron-based superconductors and copper-based superconductors. Iron-based superconductors have the highest critical temperature, reaching 56K, but their superconductivity is weak and requires higher pressure to form. Copper-based superconductors have a lower critical temperature, but they are highly superconducting and do not require high pressure to form.
The definition of superconductivity and related knowledge
1. Superconductivity refers to the phenomenon that the resistance of a material becomes zero when it is lower than a certain temperature. Superconductivity is a combination of zero resistance and complete diamagnetism. In the superconducting state, electrons inside the material no longer experience resistance and current can flow without loss. Therefore, superconducting materials can be used to create lossless cables and magnetic devices.
2. The occurrence of superconducting phenomena requires specific conditions. First, the material needs to be cooled below a certain temperature, which is called the critical temperature. Second, the material needs to withstand a certain amount of pressure, which helps electrons flow better within the material.
3. However, the realization of superconductivity requires extreme conditions, such as low temperature or high pressure. These conditions are difficult to achieve at normal temperatures and pressures, so the application of superconducting technology is still subject to certain limitations. In addition, the theoretical explanation of superconducting phenomena is not completely clear and requires further research and development.