“Quantum Trapping of Cold Neutrons with Picosecond Precision” by Prof. Malik Maaza
Webinar on The neutron is singular as it is sensitive to the four fundamental interactions: strong, weak, electromagnetic, and gravitational. This multi-sensitivity makes neutron wave-matter optics a particularly versatile tool for testing quantum mechanics and fundamental physics concepts in general. The lifetime of a free neutron defined via its beta-decay ⟨τn⟩ is of pivotal importance within the standard model & cosmology. Indeed, the precision of the neutron lifetime is paramount as it regulates the precision of the 1st element of the Cabibbo–Kobayashi–Maskawa matrix, central to the standard model.
The two major methods used to measure ⟨τn⟩ while trapping free neutrons, namely, the beam and the bottle methods, give different neutron lifetime values; ⟨τn⟩Beam ∼ 888.0 ± 2.0 s, that obtained by the bottle technique is smaller; of about ⟨τn⟩Bottle ∼ 879.4 ± 0.6 s. In addition, the persistent difference of ∼10 s persists for years, even if the two methods have been modified to enhance the experimental accuracy. This latter was shown to be enhanced if one could trap cold neutrons in nanostructured Fabry-Perot resonators. Within this webinar, the de Broglie wave-particle duality coupled to the Fermi total reflection phenomenon is discussed, in addition to the tunneling & trapping of cold neutrons in such nano-resonating cavities, allowing trapping times with a precision governed by the Heisenberg uncertainty of 10-12 s.