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Dielectric Haloscopes to Search for Axion Dark Matter: Theoretical Foundations

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 نشر من قبل Alexander Millar
 تاريخ النشر 2016
  مجال البحث فيزياء
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We study the underlying theory of dielectric haloscopes, a new way to detect dark matter axions. When an interface between different dielectric media is inside a magnetic field, the oscillating axion field acts as a source of electromagnetic waves, which emerge in both directions perpendicular to the surface. The emission rate can be boosted by multiple layers judiciously placed to achieve constructive interference and by a large transverse area. Starting from the axion-modified Maxwell equations, we calculate the efficiency of this new dielectric haloscope approach. This technique could potentially search the unexplored high-frequency range of 10--100 GHz (axion mass 40--400 $mu$eV), where traditional cavity resonators have difficulties reaching the required volume.



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