Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-parabolicity of the conduction band of wurtzite GaN   Using cyclotron resonance, we measure the effective mass, $m$*, of electrons
in AlGaN/GaN heterostructures with densities, $n_{2D}\sim
1-6\times10^{12}$cm$^{-2}$. From our extensive data, we extrapolate a band edge
mass of $(0.208\pm0.002) m_e$. By comparing our $m$* data with the results of a
multi-band \textbf{k.p} calculation we infer that the effect of remote bands is
essential in explaining the observed conduction band non-parabolicity (NP). Our
calculation of polaron mass corrections -- including finite width and screening
- suggests those to be negligible. It implies that the behavior of $m*(n_{2D})$
can be understood solely in terms of NP. Finally, using our NP and polaron
corrections, we are able to reduce the large scatter in the published band edge
mass values.

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The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg