QUantum interferometry and gravity with Positrons and LASers
03.05.19: First demonstration of antimatter wave interferometry by S. Sala, A. Ariga, A. Ereditato, R. Ferragut, M. Giammarchi, M. Leone, C. Pistillo and P. Scampoli
The scientific goal of the QUPLAS (QUantum interferometry and gravity with Positrons and LASers) antimatter experiment is the opening of two new fields of investigation in modern particle physics: antimatter interferometry, using both an elementary antiparticle (the positron, e+) and a bound e+/e- state (positronium, Ps), to test the validity of the fundamental CPT symmetry, and gravitation studies with positronium, an innovative way to inspect the Weak Equivalence Principle with a particle/antiparticle symmetric system.
The first stage of the experiment aims at the comparison of positrons and electrons interference, to compare for the first time the quantum interferometry pattern of a particle with the one of its own antiparticle. To achieve this goal, a dedicated interferometer is being assembled at the VEPAS (Variable Energy Positron Annihilation Spectroscopy) positron beamline located at the L-NESS (Laboratory for Nanostructure Epitaxy and Spintronics on Silicon) Laboratory of the Politecnico di Milano in Como (Italy).
Partial view of the positron interferometer: 1) Vacuum chamber containing the interferometer and the mu-metal shield. 2) Vacuum system. 3) x-y stage moving the absorbing target for beam size measurement. 4) Viewport for laser alignment. 5) BaF2 detector. 6) Beam control electronics. 7) Bellows used for the alignment of the interferometer chamber.
A continuous positron beam is used to produce Talbot-Lau interference by means of micrometric gratings. The particle detection relies on the employment of emulsion based high-precision position detectors, which are being developed by the physicists of the Bern group in QUPLAS. Pictures of the first interferometer prototype and the micrometric gratings are presented in this page.
An intensive R&D program has been conducted by the whole collaboration to assess the detectability of very low energy particles with emulsions and the capability to detect positrons at the keV energy scale has been successfully demonstrated.
QUPLAS Spokesperson: M.Giammarchi, INFN Milano
More details available in these articles:
- S. Sala, F. Castelli, M. Giammarchi, S. Siccardi, S. Olivares. Matter-wave interferometry: towards antimatter interferometers. J. Phys. B: At. Mol. Opt. Phys. 48, 195002 (2015) doi: 10.1088/0953-4075/48/19/195002 pdf
- S. Sala, M. Giammarchi, S. Olivares. Asymmetric Talbot-Lau interferometry for inertial sensing. Phys. Rev. A 94, 033625 (2016) doi: 10.1103/PhysRevA.94.033625 pdf
- S. Aghion, A. Ariga, T. Ariga, M. Bollani, E. Dei Cas, A. Ereditato, C. Evans, R. Ferragut, M. Giammarchi, C. Pistillo, M. Romé, S. Sala, and P. Scampoli. Detection of low energy antimatter with emulsions. JINST 11 P06017 (2016) doi: 10.1088/1748-0221/11/06/P06017 pdf
- S. Aghion, A. Ariga, M. Bollani, A. Ereditato, R. Ferragut, M. Giammarchi, M. Lodari, C. Pistillo, S. Sala, P. Scampoli, and M. Vladymyrov. Nuclear emulsions for the detection of micrometric-scale fringe patterns: an application to positron interferometry, JINST 13, P05013 (2018) doi: 10.1088/1748-0221/13/05/P05013 pdf
- S. Sala, A. Ariga, A. Ereditato, R. Ferragut, M. Giammarchi, M. Leone, C. Pistillo, P. Scampoli. First demonstration of antimatter wave interferometry, Science Adv. (I.F.: 12.804) 5eaav7610 (2019) doi: 10.1126/sciadv.aav7610 pdf
- L. Anzi, A. Ariga, A. Ereditato, R. Ferragut, M. Giammarchi, G. Maero, C. Pistillo, M. Romé, P. Scampoli, V. Toso. Sensitivity of emulsion detectors to low energy positrons, JINST 15, P03027 (2020) doi: 10.1088/1748-0221/15/03/P03027 pdf
- A.Ariga, S.Cialdi, G.Costantini, A.Ereditato, R.Ferragut, M.Giammarchi, M.Leone, G.Maero, L.Miramonti, C.Pistillo, M.Romé, S.Sala, P.Scampoli, V.Toso, The QUPLAS experimental apparatus for antimatter interferometry, Nucl. Instrum. Methods Phys. Res. A 951, 163019 (2020) doi: 10.1016/j.nima.2019.163019 pdf
More information: some presentations
- M. Giammarchi et al. (QUPLAS) Bern 2016
- S. Aghion et al. (QUPLAS) Messina 2016
- S. Sala et al. (QUPLAS) Milan 2017
- M. Giammarchi, Progress on Antimatter Interferometry (Workshop on Lorentz and CPT-violating Standard Model Extension – Indiana University) Indiana, June 2018
- M. Giammarchi et al. (QUPLAS) First Observation of Antimatter wave interference (Quantum SFB Vienna Meeting) Vienna 2018
- R. Ferragut et al. (QUPLAS) Antimatter Interferometry (International Conference on Positron Annihilation – ICPA-18), Orlando 2018
- S. Sala et al. (QUPLAS) QUPLAS: towards antimatter interferometry (Frontiers Of Matter-wave Optics: FOMO 2018) Crete, 2018
PhD Thesis: Simone Sala: QUPLAS: TOWARDS ANTIMATTER INTERFEROMETRY