Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Broken adiabaticity induced by Lifshitz transition in MoS$_2$ and WS$_2$
  single layers   The breakdown of the adiabatic Born-Oppenheimer approximation is striking
dynamical phenomenon, however, it occurs only in a handful of layered
materials. Here, I show that adiabaticity breaks down in doped single-layer
transition metal dichalcogenides in a quite intriguing manner. Namely,
significant nonadiabatic coupling, which acts on frequencies of the
Raman-active modes, is prompted by a Lifshitz transition due to depopulation
and population of multiple valence and conduction valleys, respectively. The
outset of the latter event is shown to be dictated by the interplay of highly
non-local electron-electron interaction and spin-orbit coupling. In addition,
intense electron-hole pair scatterings due to electron-phonon coupling are
inducing phonon linewidth modifications as a function of doping. Comprehending
these intricate dynamical effects turns out to be a key for mastering
characterization of electron doping in two-dimensional nano-devices by means of
Raman spectroscopy.

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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: q-fin
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
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The categories of this paper are: ao-sci
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
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The categories of this paper are: astro-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio