In the context of particle physics, a wide range of possibilities, covering low energy particle physics, precision metrology, but possibly also developments relevant for high-energy physics, has been opened by developments in quantum technologies and quantum sensing in the last decade or two. The breadth of the very dynamic developments in the area of quantum sensing far exceeds the focus of activities that can be imagined in an initial phase at CERN, although a number of areas of contact or even of overlap can already be identified at this stage. In the area of metrology, and particularly in the measurement of fields, as well as of temporal or spatial field changes, technologies such as SQUIDS, NV-diamonds, or graphene are well suited for magnetic field measurements; interferometric measurements sensitive to inertial forces may allow detecting (e.g. in the case of atom interferometers) magnetic or electric field gradients, vibrations (accelerations) or rotations (Sagnac effect). Low energy particle physics relies on the extreme sensitivity of quantum sensors to perturbations, such as very low energy deposits by microwave photons in kinetic inductance devices, TESs, or SNSPDs, or modifications of the properties of RF cavities due to interactions with a putative dark matter field. Similarly, superconducting amplifiers, electronics and detection systems allow very sensitively probing possible axion-photon conversions in strong magnetic fields. Finally, first attempts to apply quantum technologies to the needs of high energy physics, particularly in areas related to measurements of position or energy, but also more generally learning from advances and attempts at standardization in the related field of AMO, are underway. 

The following areas, mainly explored as part of physics-focused efforts at facilities like ISOLDE, the AD or non-accelerator based experiments, or as part of long-term detector R&D, provide the potential for compelling advances with, admittedly, partly still very speculative applications, particularly in the field of HEP:

    The long-term goals in the field of Quantum Sensing, Metrology and Materials are to:

    • Formalise and extend the existing catalogue of use cases and examples of possible applications of quantum sensing in areas relevant to HEP.
    • Establish links to similar initiatives starting up at university labs and form collaborations across the community.
    • Identify particularly promising technologies, focusing on a small number of developments with potential specifically for novel applications in HEP.
    • Set up common R&D projects and coordinate collaboration with other Institutes or companies to adapt or develop both the technologies themselves as well as new test systems for quantum sensing approaches and benchmark their current and potential performance.