Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High Frequency Microwave Emission of a Tri-layer Magnetic Tunnel
  Junction in the Absence of External Bias-Magnetic Field   We perform an experimental study of DC current induced microwave emission in
a magnetic tunnel junction (MTJ) consisting of three active magnetic layers.
For this tri-layer structure, in addition to a conventional bilayer orthogonal
MTJ containing a perpendicular free layer and an in-plane fixed layer, a second
perpendicular layer has been introduced. We found that the microwave emission
frequency induced by spin-transfer torque (STT) can reach as high as 6 GHz in
the absence of any applied magnetic field. Moreover, microwave emission is
observed for both current polarizations where a redshift is seen with increase
in magnitude of current. We discuss spin-dynamics of the observed
bi-directional high-frequency emission and the physical origin of the
red-shift. The distinct microwave emission properties exhibited in this
tri-layer MTJ structure could potentially be useful for future applications in
nanoscale spintronics devices such as microwave communication and neuromorphic
computing.

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The categories of this paper are: mtrl-th
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The categories of this paper are: econ
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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: nucl-th
3
The categories of this paper are: physics
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The categories of this paper are: alg-geom
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The categories of this paper are: nlin
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The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex