Single phonon excitations, with energies in the 1–100 meV range, are a powerful probe of light dark matter (DM). Utilizing effective field theory, we derive a framework to compute DM absorption rates into single phonons starting from general DM-electron, proton, and neutron interactions. We apply the framework to a variety of DM models: Yukawa coupled scalars, axionlike particles with derivative interactions, and vector DM coupling via gauge interactions or Standard Model electric and magnetic dipole moments. We find that GaAs or <math><msub><mi>Al</mi><mn>2</mn></msub><msub><mi>O</mi><mn>3</mn></msub></math> targets can set powerful constraints on a <math><mi>U</mi><mo>(</mo><mn>1</mn><msub><mo>)</mo><mrow><mi>B</mi><mo>−</mo><mi>L</mi></mrow></msub></math> model, and targets with electronic spin ordering are similarly sensitive to DM coupling to the electron magnetic dipole moment. Lastly, we make the code, phonodark-abs (an extension of the existing phonodark code which computes general DM–single phonon scattering rates), publicly available.

Germany

Andrea Mitridate

United States

Kris Pardo

Tanner Trickle

Kathryn M. Zurek

Effective field theory for dark matter absorption on single phonons

Direct detection experiments for dark matter are increasingly ruling out large parameter spaces. However, light dark matter models with particle masses <math><mrow><mo>&lt;</mo><mi>GeV</mi></mrow></math> are still largely unconstrained. Here we examine a proposal to use atom interferometers to detect a light dark matter subcomponent at sub-GeV masses. We describe the decoherence and phase shifts caused by dark matter scattering off of one “arm” of an atom interferometer using a generalized dark matter direct detection framework. This allows us to consider multiple channels: nuclear recoils, hidden photon processes, and axion interactions. We apply this framework to several proposed atom interferometer experiments. Because atom interferometers are sensitive to extremely low momentum deposition and their coherent atoms give them a boost in sensitivity, these experiments will be highly competitive and complementary to other direct detection methods. In particular, atom interferometers are uniquely able to probe a dark matter subcomponent with <math><msub><mi>m</mi><mi>χ</mi></msub><mo>≲</mo><mn>10</mn><mtext> </mtext><mtext> </mtext><mi>keV</mi></math>. We find that, for a mediator mass <math><msub><mi>m</mi><mi>ϕ</mi></msub><mo>=</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>10</mn></mrow></msup><msub><mi>m</mi><mi>χ</mi></msub></math>, future atom interferometers could close a gap in the existing constraints on nuclear recoils down to <math><mrow><msub><mrow><mover><mrow><mi>σ</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow><mrow><mi>n</mi></mrow></msub><mo>∼</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>50</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>cm</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math> for <math><mrow><msub><mrow><mi>m</mi></mrow><mrow><mi>χ</mi></mrow></msub><mo>∼</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>5</mn></mrow></msup><mi>–</mi><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>MeV</mi></mrow></math> dark matter masses.

Yufeng Du

Clara Murgui

Yikun Wang

Atom interferometer tests of dark matter