Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The nontrivial role of interfacial or film-thickness in a magnetic field
  at a one-electron and a one-Composite Fermion level   By developing a canonical approach that is exact, physically transparent and
subtly different from standard methods, we present a systematic study with
exact analytical calculations based on a Landau Level (LL) picture of the
energetics of a many-electron system in an interface (or film) and in the
presence of a uniform and perpendicular magnetic field, by seriously taking
into account the finite thickness of the Quantum Well (QW) along the field. We
find internal phase transitions (i.e. at partial LL filling) for the global
magnetization and magnetic susceptibility that are not captured by other
approaches, and that give rise to nontrivial corrections to the standard de
Haas-van Alphen periods (but in a manner that reproduces the exact quantal
deviations from the semiclassical periodicity in the limit of the full 3D
space, a problem mostly discussed in astrophysical applications and which we
independently solve analytically as well for comparison). Additional features
upon inclusion of Zeeman splitting are also found (such as certain energy
minima that originate from the interplay of QW, Zeeman and LL Physics in the
full 3D problem), while a corresponding calculation in a Composite Fermion
picture (with Lambda-Levels) leads to new predictions on magnetic response
properties of a fully-interacting electron liquid in a finite-thickness
interface; these exhibit a richer and more delicate structure than the mere
monotonic reduction of gaps with thickness reported long ago, a structure
possibly detectable with present day technology. Finally, by pursuing the same
line of reasoning for a topologically nontrivial system (with a relativistic
spectrum, spin-orbit interactions and strong coupling between thickness and
planar motion) we find evidence that similar effects may be operative in the
dimensionality crossover of 3D strong topological insulators to 2D topological
insulator quantum wells

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The categories of this paper are: physics
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: cs
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
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The categories of this paper are: nlin
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: math
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The categories of this paper are: eess
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: astro-ph