Questions tagged [fermi-liquids]
Fermi liquid theory (also known as Landau–Fermi liquid theory) is a theoretical model of interacting fermions that describes the normal state of most metals at sufficiently low temperatures. The phenomenological theory of Fermi liquids was introduced by the Soviet physicist Lev Davidovich Landau in 1956.
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Fermi liquid vs Fermi gas, when to use either one to model a metal?
I had been taught to consider electrons as a Fermi gas in order to calculate properties (like the heat capacity for instance) of metals even near $T=0K$.
However I'm now discovering Fermi liquids on ...
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What is the relation between the compressibility defined in electron liquid and that defined in thermodynamics?
In electron liquids, the compressibility $K$ is defined as $\frac{1}{K}=-V\left(\frac{\partial P}{\partial V}\right)_N=n^2\frac{\partial \mu}{\partial n}$, where $P$, $V$, $n$ and $\mu$ are pressure, ...
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What's the exact definition for strong correlation in condensed matter physics?
Can we judge or define the strong correlation (for electron system) in condensed matter physics just by the competition of kinetic energy and interaction energy term in the total Hamiltonian? I mean ...
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Discontinuity of Fermi liquid occupancy
In Fermi liquid theory, the electron spectral function is often represented by $$A(k,\omega) = Z\delta(\omega-\epsilon_k)\ + \text{incoherent background} $$ where $Z$ is the weight in the ...
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Hall effect at finite temperature in conventional metals
There are lots of measurements showing strong temperature ($T$) dependence of Hall coefficient ($R_H$) in correlated materials (eg. cuprate superconductors and other oxide materials) and such plots ...
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Why does the free electron theory of metals work?
Free electron theory of metals works unreasonably well in spite of the fact that we neglect the Coulomb repulsion between the electrons. Is there deeper reason why this should work? Somewhere I heard ...
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Failure of Hertz-Millis-Moriya theory for quantum phenomena
In the quantum critical phenomena of condensed matter, the earlier work by Hertz, Moriya and Millis develope the the Hertz-Millis-Moriya (HMM) theory of quantum phase transition.
Naively, they ...
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Fermi "surface" at finite temperature and its measurement in the lab
As we increase the temperature, we know the sharp Fermi surface at zero temperature becomes smeared out at finite temperature $T>0$. (Just think of the Fermi-Dirac distribution, there will be no ...
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The validity of infinite many Conformal Field Theories on the Fermi surface
The naive $2$-dimensional Fermi sea in $k$-space (with a convex structure and positive Gaussian curvature, some nice properties, etc) in $2+1$-dimensional spacetime may be viewed as an infinite ...
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Conventional Landau orders and non-conventional orders in the pseudogap of cuprate
What kind of conventional Landau orders have been seen in the pseudogap phase of cuprate? Such as Spin-Density Wave, Charge-Density Wave, etc? What are the most influential/representative journal Refs ...
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Why is the density of the Fermi gas in a neutron star not changing the potential depth caused by the strong nuclear interaction?
In some textbooks, the neutron star is explained as a degenerate Fermi gas. To calculate the degenerate pressure of the neutron fermi gas the average Energy of a neutron, U is calculated when the ...
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The "dangerous" fixed points for Renormalization Group
What is the definition of dangerously irrelevant renormalization-group (RG) fixed point?
What are some examples of dangerously irrelevant RG fixed points?
Do we also have the use of dangerously ...
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Total energy of a simple fermi gas
I am a student and working on a fermi gas problem.
I already figured out how to calculate the fermi energy of my idealized (no interactions) fermi sphere gas of radius R, but now I want to find out ...
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Experimental confirmation of the finite jump of the occupation number at the Fermi surface
It is a well-known result in Fermi-liquid theory that the occupation number has a finite jump at the Fermi surface. But, is it confirmed experimentally?
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What is the shape of a band electron in momentum space?
Band electrons occupy adjacent sharply defined momentum states that in xyz space take the form of a spectrum of wave functions. These wave functions span the entire xyz volume of any compact unit of ...
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