Superconductors ✖ Bach

Background reading music curated for this article is available at the bottom. Click to enjoy

In the physics world, especially in the field of electromagnetics, most experiments suffer from the flaw of the existance of resistance within all apparatus. Many wonders if there is a way to eliminate such resistance. Here I would say, of course. This issue is directly addressed by the technology of superconductivity.

01 Resistance and Superconductivity

I would love to cut in the topic with a brief explanation of the origin of resistance. All substances are made from atoms, and atoms comprises of electrons and nucleons. It is commonly accepted that electrons are free moving while nucleons are relatively stationary. As the material is connected to a circuit, there exists electric potential difference, commonly known as voltage. This gives the electrons a Coulomb force, urging them to move in a specific direction, forming an electric current. However, there exists collisions between stationary nucleons and free-moving electrons. This phenomenon hinders the constant acceleration of electrons and increase in current. This is how resistance emerges in regular conducting materials.

Formation of Resistance

Just as it is named, superconductive materials have such extraordinarily magnificent conducting abilities that resistance can barely exist. Superconductive materials eliminate resistance by pairing electrons into Cooper pairs. Such pairs allow electrons to flow through the material without colliding with nucleons. These pairs move in a coordinated, frictionless way, preventing the scattering that causes resistance and heat in normal conductors.

Cooper Pairs

02 Types of Superconductors

There are two types of superconductors technologies available till now, Type I and Type II. 

Superconductor Properties

Type I superconductors are commonly regarded as low-temperature superconductors. 

Type I Superconductor

They have a single critical magnetic field; below this field they exhibit perfect diamagnetism (complete expulsion of magnetic fields via the Meissner effect), but above it they sharply lose their superconductivity. These so-called “soft” superconductors operate only at very low temperatures (usually under about 10 K) and are relatively sensitive to external magnetic disturbances.

On the other hand, Type II superconductors — which are often alloys or complex ceramic oxides — feature two critical magnetic fields, Hc1and Hc2. Between these fields they enter a “mixed state” where magnetic flux penetrates the material in quantized vortices, so they don’t fully expel the field, but still remain superconducting overall. 

Type II Superconductor

Because of this, Type II superconductors (“hard” superconductors) can sustain much higher magnetic fields and operate at comparatively higher temperatures, making them highly suitable for practical applications like MRI magnets, power cables, and particle accelerators. Compared to Type I, Type II can work at a relatively higher temperature (above 10 K) and thus are called high-temperature superconductors.

03 Exising Barriers

However, all of the two superconductors mentioned above requires extremely low temperature (10 K, for example, -263℃). It is obviously not achievable under normal conditions (STP, standard temperature and pressure). Are there any materials that can be superconductive in relatively achievable conditions. 

This idea is called room-temperature superconduction. This, currently is not possible. The first limitation is that the Cooper pairs can be formed if and only if the temperature of thre substance is low, so that the average kinetic energy is low. Also, the lack of high pressure also hinders the existence of room-temperature superconductivity. Some recently discovered “high-temperature superconductors” work only at pressures higher than those at the Earth’s core (millions of atmospheres). These conditions stabilize special hydrogen-rich structures that allow superconductivity, but they cannot exist at normal pressure.

Conclusion and Music

Despite the fact that room-temperature superconductivity is not possible now, it is under high expectations. In the near future, the possibility of electricity transfer without energy loss is highly positive.

I would love to use Johann Sebastian Bach — Cello Suite No. 1 in G Major, Prelude to end this episode. 

Johann Sebastian Bach — Cello Suite No. 1 in G Major

3:06

The prelude unfolds in one continuous, smooth stream — no musical resistance, mirroring superconducting current; the clarity and mathematical structure reflect the logical, elegant physics described previously; its simplicity mirrors the fundamental principles (resistance, electron collisions, Cooper pairing).

Enjoy ~~