prompter: What are the materials with transition temperature between 20K and 40K

assistant: Some superconductors have a transition temperature between 20 degrees Kelvin and 40 degrees Kelvin:

* High-temperature superconductors (HTS): HTS materials such as YBa2Cu3O7-x (YBCO), Bi2Sr2CaCu2O8+x (BSCCO), and Tl2Ba2Ca2Cu3O10+x (Tl-1223) have transition temperatures between 20K and 40K.
* Iron-based superconductors: Iron-based superconductors such as Sodium iron arsenide (NaFeAs) which has a transition temperature of 20 K. LaFeAs(O,F) and Ba(Fe1-xTx)2As2 (where T = Co, Ni) have transition temperatures between 20K and 40K.
* Ruthenates: Ruthenates such as Sr2RuO4 have a transition temperature of around 1.5 K, but their doped counterparts, such as Sr3Ru2O7 and SrRuO3, have transition temperatures in the range of 20K to 40K.
* Magnesium diboride (MgB2): MgB2 is a relatively new superconductor with a transition temperature of around 39K.
* Vanadium dioxide (VO2): VO2 undergoes a metal-insulator transition around 68°C (341K), but doped VO2 can exhibit a transition temperature in the range of 20K to 40K.
* Cesium fulleride (Cs3C60), a type of organic superconductor that has a transition temperature of 38 K.
* Rubidium-doped carbon-60 (C60RbX), a similar organic superconductor that has a transition temperature of 28 K.
* Potassium-doped carbon-60 (C60K3) comes very close, with a transition temperature of 19.8 K.

prompter: Could you explain what each of those substances are like I'm 5 years old, and why super conductors matter?

assistant: The materials with transition temperature between 20K and 40K are known as "low-temperature superconductors". Examples of such materials include niobium-titanium (NbTi), niobium-tin (Nb3Sn), and magnesium diboride (MgB2). These materials are used in various applications such as MRI machines, particle accelerators, and fusion reactors.

prompter: could you tell me what superconductors are and in what way low-temperature superconductors are special among them?

assistant: Superconductors are materials that can conduct electricity without any resistance. They are able to achieve this property when they are cooled to very low temperatures, typically below a certain critical temperature, which is specific to each type of superconductor.

Low-temperature superconductors (LTSC) are a special class of superconductors that achieve superconductivity at temperatures close to absolute zero (0 Kelvin or -273.15 degrees Celsius). These materials typically have critical temperatures below 30 Kelvin (-243.15 degrees Celsius) and include metals such as lead and mercury.

The low critical temperatures of LTSCs make them more challenging to use in practical applications than high-temperature superconductors (HTSC), which can achieve superconductivity at much higher temperatures. However, LTSCs have certain advantages over HTSCs, such as higher critical magnetic fields and higher critical current densities. These properties make LTSCs ideal for applications that require strong magnetic fields, such as in MRI machines and particle accelerators. They are also used in certain electronic devices, such as high-speed electronic filters, because of their fast response times and low energy losses.

assistant: Superconductors are materials that can conduct electricity with zero electrical resistance, meaning that electric current can flow through them without any loss of energy. This remarkable property makes superconductors very useful in a wide range of applications, such as in magnetic resonance imaging (MRI) machines, particle accelerators, and power transmission lines.

A superconductor is generally considered low-temperature if it reaches a superconducting state at a temperature of below 30 K (−243.15 °C). They are cooled mainly by liquid helium (critical temperature > 4.2 K), which is a lot more difficult and energy consuming than reaching the temperature for high-temperature superconductors. For high-temperature superconductors it's often sufficient to cool them using liquid nitrogen (critical temperature > 77 K).

prompter: Are there any room temperature super conductors?

assistant: Superconductors are materials that have the ability to conduct electricity with zero electrical resistance, which means they can conduct electricity without losing any energy due to resistance. They also have other unique properties such as the Meissner effect, which causes them to expel magnetic fields.

Low-temperature superconductors are a special class of superconductors that require very low temperatures to exhibit their superconducting behavior. They typically have a critical temperature below 30 K (-243.2°C), and some even below 10 K (-263.2°C). This is in contrast to high-temperature superconductors, which have critical temperatures above 30 K.

Low-temperature superconductors are special among superconductors because they have been used extensively in a wide range of applications, such as in superconducting magnets used in magnetic resonance imaging (MRI) machines and particle accelerators. They are also used in power transmission, high-speed computing, and other advanced technologies.

However, low-temperature superconductors also have some limitations. They require cooling with liquid helium or other cryogens, which can be expensive and require specialized equipment. They also have relatively weak superconducting properties, which means they cannot carry as much current or generate as strong of a magnetic field as high-temperature superconductors.

High-temperature superconductors were discovered in the 1980s, and they have the potential to revolutionize a variety of technologies. However, they are still in the early stages of development, and they are not yet as widely used as LTS superconductors.

One of the main advantages of HTS superconductors is that they can operate at much higher temperatures, which makes them more versatile. This means that they do not require cooling with liquid helium, which can be expensive and require specialized equipment. HTS superconductors also have the potential to carry more current and generate stronger magnetic fields than LTS superconductors.

However, HTS superconductors also have some limitations. They are still in the early stages of development, and they are not yet as reliable as LTS superconductors. They are also more expensive than LTS superconductors.

Researchers are working to develop new HTS materials that are more reliable and easier to manufacture. If they are successful, HTS superconductors could revolutionize a variety of technologies, including power transmission, transportation, and medical imaging.

***TLDR***: 
Superconductors are materials that conduct electricity with zero resistance. Low-temperature superconductors require very cold temperatures to work, while high-temperature superconductors can work at much higher temperatures. LTS superconductors are well-understood and relatively easy to manufacture, while HTS superconductors have the potential to overcome the limitations of LTS superconductors. Researchers are working to develop new HTS materials that are more reliable and easier to manufacture.