Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Terahertz Magneto Optical Polarization Modulation Spectroscopy   We report the development of new terahertz techniques for rapidly measuring
the complex Faraday angle in systems with broken time-reversal symmetry using
the cyclotron resonance of a GaAs two-dimensional electron gas in a magnetic
field as a system for demonstration of performance. We have made polarization
modulation, high sensitivity (< 1 mrad) narrow band rotation measurements with
a CW optically pumped molecular gas laser, and by combining the distinct
advantages of terahertz (THz) time domain spectroscopy and polarization
modulation techniques, we have demonstrated rapid broadband rotation
measurements to < 5 mrad precision.

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The categories of this paper are: supr-con
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The categories of this paper are: math-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: nucl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
1
The categories of this paper are: cs
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The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
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The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc