29 jul 2025 - 18:25 CET

Superconducting qubits are the leading candidate platform on which to build quantum processors owing to a continuous development of many fronts of the technology: enhanced material quality, noise source mitigation, advanced quantum circuit designs, novel cryogenic technology, etc. The current advanced state of superconducting qubits permits envisioning them towards applications beyond quantum computing. An important direction of application is quantum sensing, given the high sensitivity of qubit devices to environmental fluctuations. In particular, superconducting qubits are the best existing single microwave photon detectors. This permits using qubits to detect signals in the form of individual microwave photons appearing from interactions through fundamental physics effects, such as dark matter axions [1], but also graviational waves.

In this project, a first generation of dark matter axion detectors based on superconducting qubits will be built. The challenge in achieving a highly efficient detector is the combination of cavity QED physics with qubits to detect photons and the resilience of qubits under strong magnetic fields, which are necessary to achieve the axio-to-photon conversion. The project will focus on the characterization of the detector specifications, particularly the study of the baseline of dark count events and their relation with ionizing radiation impacts on the chip [2].

The PhD thesis will be framed in the context of the RADES collaboration, through the QRADES Quantera project funded by the Spanish Ministry of Science and Innovation, and by the EU project SUPREME. The project is expected to begin in Q1 2026. Interested candidates may submit an application with a CV including transcript of university records (both undergraduate and master degrees), a letter of motivation (1 page) and at least 2 letters of recommendation.

More information on this position and the QCT group can be found here: https://qct.ifae.es/

[1] A. Dixit et al., Phys. Rev. Lett. 126, 141302 (2021)
[2] E. Bertoldo et al., New J. Phys. 27, 023014 (2025)

Web: https://qct.ifae.es/positions/