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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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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Is that possible to derive Landau-Fermi liquid theory from microscopic equation?
This question arises from reading Wen's book "Quantum Field Theory of Many-body Systems (Oxford 2004)" p204
To appreciate the brilliance of Landau-Fermi liquid theory, let us look at the
many-...
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What is a marginal fermi liquid in a nutshell?
I would like to know what are the main differences between the normal Fermi liquid theory and a marginal fermi liquid theory. What kind of systems can be described by the marginal liquid theory? What ...
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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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Hertz-Millis theory and quantum criticality
Hartz-Millis(HM) theory is a model which exhibits quantum phase transition. The HM action following Altland & Simons is given by
$$
S = \frac{1}{\beta}\sum_{\omega_{n}}\int \frac{d^d q}{(2\pi)^d}\...
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How is mass renormalization in heavy fermion materials differnt from a normal Fermi Liquid?
In normal fermi liquid theory, I saw that the mass is renormalized as
$$ \frac{m*}{m}=1+\frac{F_0}{3} $$
Recently I saw a couple talks on heavy fermion materials. One described, the fermi liquid ...
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Feedback effect of interactions : No interactions between quasiparticles if no external field?
I am working with Coleman "Introduction to many body physics".
In the chapter 7 (pages 131-132) we deal with Fermi liquid and they talk about the Feedback effect of interactions of the quasi ...
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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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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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Pomeranchuk Effect
Pomeranchuk effect poses a paradox of order by disorder phase-transition. The liquid Helium-3 is in a liquid form close to absolute temperature. For high enough pressure, as you increase the ...
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Momentum distribution Fermi liquid and spectral representation
In a Fermi liquid the momentum distribution shows a jump at the Fermi surface, i.e.
\begin{equation}\langle n_{k_F-\delta k} - n_{k_F+\delta k}\rangle = Z_{k_F}\end{equation}
with $Z_k$ the strength ...
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Infrared cutoff in the Kramers-Kronig relation for the marginal Fermi liquid
I am going through Andre-Marie Tremblay's derivation of the real part of the self energy in his lecture notes on the many-body problem. On page
254, if we take the imaginary $\Sigma''(k,\,\omega)\sim \...
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The formula for the average number of fermions $\langle N \rangle$
In the context of Fermi gases (or fluids in general), one would typically in the grand-canonical formalism use the formula
$\langle N \rangle = -\frac{\partial \psi}{\partial \mu}$, where $\psi$ is ...
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Why do we study fermi system at half-filling state?
I am reading Shankar's paper on RG for interacting fermions and in the paper, all study is done on Fermi system at half-filling state. Is there any specific reason why? Also, does it make a different ...
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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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