A Penning trap single-photon counter for axion detection

TL;DR

This paper proposes a novel single-photon detection method using a Penning trap electron for axion dark matter searches, overcoming quantum noise limits and enabling detection in higher mass ranges.

Contribution

It introduces a new phase-sensitive axial detection technique with axial-magnetron amplification for high-frequency photon counting in Penning traps, advancing axion detection capabilities.

Findings

The proposed detector can operate effectively at 30-60 GHz.

It surpasses quantum noise limits for photon detection.

It is suitable for high-mass axion searches.

Abstract

Discovering the microscopic composition of dark matter is one of the most important open problems in physics today. Axions are a leading candidate to be dark matter; however, a search of the full range of all likely axion masses is hampered by the standard quantum noise limit. This makes haloscope searches for axions with masses above 0.1 meV unfeasible with current technologies. To overcome this limitation, we propose a new photon counting technique designed to operate at 30-60 GHz for detecting axions with masses between 0.124 meV and 0.248 meV, based on a single electron in a Penning trap. The electron cyclotron mode absorbs microwave photons, and, via the continuous Stern-Gerlach effect, this absorption imparts a measurable phase shift onto the axial motion. In this paper, we comprehensively analyze this photon detection method. We introduce a new type of fast, phase-sensitive axial detection technique, using axial-magnetron parametric amplification to overcome detector Johnson noise and cancel associated frequency shifts. This method may find other applications in precision Penning trap frequency measurements. We compare the efficiency of the electron single-photon counter with an ideal device, and find that our proposed photon counter has sufficient performance to search for high mass axions.