Superradiant Neutrino Lasers from Radioactive Condensates

Superradiance emerges from collective spontaneous emission in optically pumped gases, and is characterized by photon emission enhancements of up to <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mfrac><a:mrow><a:mn>1</a:mn></a:mrow><a:mrow><a:mn>4</a:mn></a:mrow></a:mfrac><a:msup><a:mrow><a:mi>N</a:mi></a:mrow><a:mrow><a:mn>2</a:mn></a:mrow></a:msup></a:mrow></a:math> in an <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mi>N</c:mi></c:math> atom system. The gain mechanism derives from correlations developed within the decay medium rather than from stimulated emission as in lasing, so an analog of this process should be possible for fermionic final states. We introduce here the concept of superradiant neutrino emission from a radioactive Bose Einstein condensate, which can form the basis for a superradiant neutrino laser. A plausible experimental realization based on a condensate of electron-capture isotope <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mrow><e:mmultiscripts><e:mrow><e:mi>Rb</e:mi></e:mrow><e:mprescripts/><e:none/><e:mrow><e:mn>83</e:mn></e:mrow></e:mmultiscripts></e:mrow></e:math> could exhibit effective radioactive decay rates accelerated from 86.2 days to minutes in viably sized rubidium condensates of <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:msup><g:mn>10</g:mn><g:mn>6</g:mn></g:msup></g:math> atoms.