Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Enhanced Thermoelectric Efficiency via Orthogonal Electrical and Thermal
  Conductances in Phosphorene   Thermoelectric devices that utilize the Seebeck effect convert heat flow into
electrical energy and are highly desirable for the development of portable,
solid state, passively-powered electronic systems. The conversion efficiencies
of such devices are quantified by the dimensionless thermoelectric figure of
merit (ZT), which is proportional to the ratio of a device's electrical
conductance to its thermal conductance. High ZT (>2) has been achieved in
materials via all-scale hierarchical architecturing. This efficiency holds at
high temperatures (700K~900K) but quickly diminishes at lower temperatures. In
this paper, a recently-fabricated two-dimensional (2D) semiconductor called
phosphorene (monolayer black phosphorus) is assessed for its thermoelectric
capabilities. First-principles and model calculations reveal that phosphorene
possesses spatially-anisotropic electrical and thermal conductances. The
prominent electrical and thermal conducting directions are orthogonal to one
another, enhancing the ratio of these conductances. As a result, ZT can reach
2.5 (the criterion for commercial deployment) along the armchair direction of
phosphorene at T=500K and is greater than 1 even at room temperature given
moderate doping (~2 x 10^16 m-2). Ultimately, phosphorene stands out as an
environmentally sound thermoelectric material with unprecedented qualities:
intrinsically, it is a mechanically flexible material that converts heat energy
with high efficiency at low temperatures (~ 300K) - one whose performance does
not require any sophisticated engineering techniques.

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The categories of this paper are: nucl-ex
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The categories of this paper are: cs
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
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The categories of this paper are: chem-ph