A concise introduction and explanation of the different experimental techniques used in the study of neutron EDM are provided in this research work. These techniques include the room-temperature experiment, Ramsey’s technique, and the mercury magnetometer. A brief discussion of the prevailing systematic uncertainties such as the geometric phase effect is also included. A recent neutron EDM experiment, which is more sensitive and still in progress is also incorporated and detailed in this study.
For over 50 years, the quest for an electric dipole moment (EDM) of a neutron has been a great endeavor in the field of physics.3 4 5 Ramsay’s search for a permanent EDM in the 1950’s leads the way to what seems to be an endless pursuit. Experimental sensitivity has increased significantly; in fact, it improved by more than 106 factor.6 An impressive breakthrough in improving the experimental sensitivity, accountable for every eight years or so, is shown in Figure 1.7 Despite such remarkable accomplishment, there was no EDM ever observed.
The reason for this apparently obsessive behavior by a small group of dedicated physicists is that the observation of a nonzero neutron EDM would be evidence of time reversal violation and for physics beyond the so-called standard model of electroweak interactions. An essential point is that the standard model predictions of the magnitude of time reversal violation are inconsistent with our ideas of the formation of the universe; namely, the production of the presently observed matter-antimatter asymmetry requires time reversal violation many orders of magnitude greater than that predicted by the standard model.
According to Steven Weinberg, the electric dipole moments may offer one of the most thrilling prospects for progress in particle physics; a bright future awaits prospective experiments because calculating electric dipole moments have been progressive recently.