The Dynamics of Cold Rubidium 87 Atoms Under an Electro-magnetic Field

  Yair Salem   ,  Dr. Orel Bechler  ,  Prof. Barak Dayan  
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel

The cutting edge of science today, from astronomy to microbiology, is based on computers, but even computers have their limits. The classical bit, the most basic building block of the classical computer, can be in one of two states- 0 or 1. Unlike the classical bit, the qubit (quantum bit) contains quantum properties, such as super-position and quantum entanglement. These properties allow, in theory, to calculate certain calculations much faster.
In order to develop quantum computers, scientists must be able to control internal energy levels, the temperature and velocity of quantum systems and know how they interact and behave.
One example of such behavior is called Rabi oscillations. When a cluster of atoms encounters an electro-magnetic wave, a cyclic transition occurs in the population of electrons in the energy levels of the atoms, with a similar shape to a sine wave.
The goal of this research is to record such oscillations by measuring the dynamics of Rubidium 87 atoms under an electro-magnetic field.
To measure the dynamics of Rubidium 87 atoms, an RF (radio frequency) pulse, was transmitted through the atomic ensemble. Several laser pulses were then used to measure the atomic population over time.
The analysis and processing of the results showed a decaying sine wave. This indicates that we can use RF pulses to steadily transfer the electrons of Rubidium 87 between the atomic ground states.
We also found that using an RF pulse to transfer the electrons has some advantages over other optical methods. This method is more stable and shows a slower transfer of the electrons, and a smaller chance to lose a photon in the process. This longer lifetime potentially allows for longer experiments and the ability to conduct more complex atomic manipulations over time, adding more tools to our toolbox in the research of quantum technology.