Fermi Liquid Theory

1. Name-:Tripti
FERMI LIQUID THEORY

2. Fermi Liquid Theory is a fundamental framework in
condensed matter physics that describes the behavior of
electrons in a solid or liquid metal. It was developed by Lev
Landau and provides a comprehensive understanding of how
electrons interact with each other in these systems.
Introduction

3. Basic Concepts of Fermi
Liquid Theory
Fermi Surface Quasiparticles
Conservation
Laws
Landau’s
Interaction
Parameter

4. Quantum statistics categorizes particles into two main classes based
on their behaviour and properties at the quantum level.
1. Fermions: Fermions are particles that obey Fermi-Dirac statistics.
no two identical fermions can occupy the same quantum state
simultaneously.
2. Bosons: Bosons are particles that obey Bose-Einstein statistics.
Unlike fermions, multiple identical bosons can occupy the same
quantum state simultaneously.
Quantum Statistic and fermi Dirac
Distribution

5. The Fermi-Dirac distribution function describes how
fermions, such as electrons, are distributed among the
available energy states in a quantum system at a given
temperature (T). It was formulated independently by Enrico
Fermi and Paul Dirac.
Fermi-Dirac Distribution

6. Key Characteristics of the Fermi-Dirac
Distribution
Exclusion Principle Temperature Dependence
Chemical Potential Step-like Behaviour
Characteristics

7. Applications of Fermi Liquid
Theory
Electrical
conductivity
•Fermi Liquid
Theory provides
insights into the
electrical
conductivity of
metals. It explains
how electron-
electron
interactions affect
the flow of
electric current.
Superconductivity
•Fermi Liquid
Theory plays a
role in explaining
the behaviour of
superconductors,
which are
materials with
zero electrical
resistance at low
temperatures.
Material
Science
•Researchers use
Fermi Liquid
Theory to study
and design novel
materials with
specific electronic
properties.
Nuclear
Physics
•Fermi Liquid
Theory has
applications in
nuclear physics,
where it helps
describe the
behavior of
nucleons (protons
and neutrons) in
atomic nuclei.

8. Limitations
Weakly Interacting Systems: In strongly correlated systems,
where electron-electron interactions are strong and cannot be
treated perturbatively, Fermi Liquid Theory may not be
applicable.
High Temperatures: At high temperatures, especially
above the Fermi temperature, the assumptions
underlying the theory may break down, and deviations
from Fermi Liquid behaviour can occur.
Non-Equilibrium Conditions: It may not fully capture the
behaviour of electrons in non-equilibrium situations, such
as during ultrafast laser experiments or in devices
operating far from equilibrium.
Beyond Three Dimensions: Fermi Liquid Theory is primely
developed for three dimensional systems, it becomes less
accurate when applies to lower dimensional systems.

9. THANK YOU