Research

My research is part of the ALPHA experiment at CERN, which produces and studies magnetically trapped antihydrogen — the simplest pure-antimatter atom. By performing precision spectroscopy on antihydrogen and comparing it with hydrogen, we can test fundamental symmetries of nature, including CPT invariance and the weak equivalence principle.

My work has two main threads.

Cryogenic fluorescence detection

I led the development and integration of a cryogenic silicon photomultiplier (SiPM) detection system operating at 4 K inside a Penning trap. This system serves two purposes: real-time plasma diagnostics of Be⁺ ions used for sympathetic cooling of antihydrogen, and direct fluorescence detection of antihydrogen photons. SiPMs offer single-photon sensitivity and near-zero dark noise at cryogenic temperatures, making them well suited to the extremely low signal rates involved. I designed the Penning trap, SiPM arrays, cryogenic circuitry and front-end readout electronics and characterised both the Hamamatsu and Onsemi SiPM models across the full cryogenic operating range.

Excited-state spectroscopy of antihydrogen

I lead the analysis of the first measurement of an excited-state transition in antihydrogen: the 2S–2P transition. This is the first observation of a lineshape from an antimatter atom that probed by first exciting antihydrogen to the metastable 2S state using two counterpropagating 243 nm photons, and subsequently driving the 2S–2P transition with microwaves. The line centre is extracted from the resulting atom loss through a detailed lineshape analysis.

Publications

Talks and conferences