Why do strange metals exhibit non-Fermi liquid behavior

Learn about the mysterious behavior of strange metals in condensed matter physics. Explore why they exhibit non-Fermi liquid behavior and the leading theories behind it.

Why do strange metals exhibit non-Fermi liquid behavior?

The behavior of strange metals has long been a mystery in the world of physics. These metals exhibit properties that are difficult to explain using traditional theories of condensed matter physics. One of the most interesting phenomena observed in strange metals is their non-Fermi liquid behavior. In this article, we will explore what strange metals are and why they exhibit non-Fermi liquid behavior.

What are Strange Metals?

Strange metals are a special type of metal that is characterized by their unusual electrical conductivity. These metals conduct electricity in a way that is different from traditional metals. In traditional metals, the electrical conductivity is proportional to the number of electrons that are present in the material. However, in strange metals, the electrical conductivity does not follow this rule.

Strange metals are found in a variety of different materials, including some high-temperature superconductors and heavy fermion metals. These metals are often studied because they exhibit a number of unusual properties that are not seen in other materials. These properties include non-Fermi liquid behavior, anomalous Hall effect, and unconventional superconductivity.

Why Do Strange Metals Exhibit Non-Fermi Liquid Behavior?

The question of why strange metals exhibit non-Fermi liquid behavior is still an open problem in condensed matter physics. However, there are several theories that have been proposed to explain this behavior.

The Role of Strong Electron Correlations

One of the leading theories for why strange metals exhibit non-Fermi liquid behavior is the role of strong electron correlations. In traditional metals, the interactions between electrons are weak, and the electrons behave like non-interacting particles. However, in strange metals, the interactions between electrons are much stronger, and the electrons appear to be interacting in a highly correlated way.

This strong correlation between electrons can lead to the breakdown of the Fermi liquid description of the metal. In traditional metals, the interactions between electrons are weak enough that the electrons can be treated as independent quasiparticles. However, in strange metals, the strong interactions between electrons can lead to the breakdown of this quasiparticle description.

This breakdown of the quasiparticle description can result in the absence of a well-defined Fermi surface and the emergence of non-Fermi liquid behavior.

The Role of Quantum Criticality

Another theory for why strange metals exhibit non-Fermi liquid behavior is the role of quantum criticality. Quantum criticality is a phenomenon that occurs when a material undergoes a phase transition at absolute zero temperature. At the quantum critical point, the material can exhibit unusual properties that are not seen in other materials.

In strange metals, it is possible that the non-Fermi liquid behavior is a result of the proximity to a quantum critical point. As the material approaches the quantum critical point, the interactions between electrons can become stronger, leading to the breakdown of the quasiparticle description and the emergence of non-Fermi liquid behavior.

The Role of Disorder

A third theory for why strange metals exhibit non-Fermi liquid behavior is the role of disorder. Disorder can occur in a material when there are impurities or defects present in the crystal structure. In strange metals, it is possible that the non-Fermi liquid behavior is a result of the disorder in the material.

Disorder can lead to a breakdown of the quasiparticle description and the emergence of non-Fermi liquid behavior. The presence of disorder can also lead to the formation of new electronic states that are not present in traditional metals.

Conclusion

In conclusion, the behavior of strange metals is a fascinating area of research in condensed matter physics. Strange metals exhibit a number of unusual properties, including non-Fermi liquid behavior, that are not seen in other materials. While the question of why strange metals exhibit non-Fermi liquid behavior is still an open problem, there are several theories that have been proposed to explain this behavior. Further research in this area may lead to new insights into the behavior of materials at the atomic scale.