Since the concept of Rabi flopping emerged in the first half of the 20th century, two-level quantum mechanical systems have been accurately explained using an atom as a "mixed state" between both levels. An incoming oscillating light field at a resonant frequency causes the population in either energy level, or "state", to oscillate between each other at a so-called Rabi frequency.

However, not all two-level transitions are the same, as some transitions are extremely strong (or probable) while others are much weaker (improbable). This means that if one is interested in exploring a "forbidden" transition between initial state i and final state j, one must first find the alternate pathways (other than going directly from i to j) going through intermediate states k,m.. etc. For my project, I am using a sample optical pathway for krypton between its ground state and its first metastable state (1->3->10->2), chosen from the equivalent optical pathways below.

Once these alternate pathways are identified, it is important to compare the efficiency of population transfer for equivalent pathways. Using density matrix formulation, these n-level quantum mechanical pathways can be modeled with coupled linear differential equations based on optical and atomic input parameters.

My results show that the efficiency of transitions depends strongly upon laser intensity, resonance detuning, and collision rate. The image below shows the result of a global sensitivity analysis which shows the sensitivity indices of the parameters of my model.

Further results are bound by dissemination restrictions, so if you are interested in finding out more please contact me at milad.aboudakka@adelaide.edu.au.