Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Intersubband magnetophonon resonances in quantum cascade structures   We report on our magnetotransport measurements of GaAs/GaAlAs quantum cascade
structures in a magnetic field of up to 62 T. We observe novel quantum
oscillations in tunneling current that are periodic in reciprocal magnetic
field. We explain these oscillations as intersubband magnetophonon resonance
due to electron relaxation by emission of either single optical or acoustic
phonons. Our work also provides a non-optical in situ measurement of
intersubband separations in quantum cascade structures.

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The categories of this paper are: math-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: physics
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
2
The categories of this paper are: math
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: funct-an
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc