Ramsey Spectroscopy in Cold Atoms

• Grant number: 25/21768-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2025
• End date: October 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Physics - Atomic and Molecular Physics
• Principal Investigator: Daniel Varela Magalhães
• Grantee: Felipe Oliveira Leiras da Mota
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 25/11303-1 - Ramsey Spectroscopy in Cold Atoms, AP.R

Abstract

Cold atoms have been used for decades for high-resolution measurements in time metrology. Atomic clocks utilize Ramsey Separated Oscillatory Field Spectroscopy to achieve extremely precise timekeeping. This approach is used in Primary Frequency Standards called Atomic Fountains. This experimental apparatus is responsible for one of the smallest uncertainties in measuring the "second" standard. This development is attributed to the narrow velocity distribution of cold atoms during the Atomic Interrogation process of the Clock Transition.Studying the interaction and expansion processes of atoms with the interrogation field is essential for a more refined characterization of the sample and the effects arising from its momentary state, such as the temperature and velocity of the atomic cloud during cold collisions. In this regard, the spectral signature of separated-field atomic interrogation, called Ramsey fringe, can become a valuable tool for this in-depth study. In this sense, developing models capable of transforming them into diagnostic tools becomes extremely useful for establishing improved techniques for interrogating atoms, in order to use the laboratory we have in the group as an experimental tool.