Ultra-low noise magnetic environments
Lead Research Organisation:
Imperial College London
Department Name: Physics
Abstract
The aim of this proposal is to develop an environment where electric and magnetic fields are controlled at the level needed for the next generation of quantum sensors. These sensors are being developed both for commercial applications and for precision measurements that test fundamental theories of physics. To reach their ultimate sensitivity, they must operate in extremely low noise environments. Thus, our project is designed to remove a barrier that is now inhibiting progress in quantum technology and our ability to test new theories.
Our objective is to design, develop and characterize a magnetically-shielded vacuum cell where the background magnetic field and magnetic noise are reduced to extremely low values. We aim to generate large electric fields inside this cell, without compromising the magnetic noise. This calls for careful choices of materials and construction methods and measurements of electric currents at the extreme limits of sensitivity. Finally, we aim to integrate magnetic field probes within the cell for in situ, real-time field measurement and control. The output will be an instrument capable of sensing tiny fields and forces beyond the current state of the art.
One application of such an apparatus in fundamental science is to measure the roundness of the electron, which is measured through its electric dipole moment (eEDM). A non-zero eEDM indicates a violation of time-reversal symmetry, which is crucial in understanding why matter prevails over antimatter in the Universe. To dramatically improve the measurement precision, we have developed transformative techniques to produce trapped ultracold molecules. We have completed a design study of this approach where all the steps are simulated, and have demonstrated most of the key steps with a testbed molecule. The apparatus, which provides precisely controlled magnetic and electric fields, will be the crucial final piece of our new approach, facilitating future experiments to determine electron roundness with unprecedented precision, several hundred times better than before. Such measurements have the potential to discover new particles beyond the reach of particle colliders and shed light on the matter-antimatter asymmetry in the Universe.
Beyond EDM experiments, the apparatus will benefit other tests of fundamental physics using quantum technologies. It will enhance experiments with atom interferometers to probe gravitational waves and ultra-light dark matter, and contribute to atomic clocks to measure varying fundamental constants. The collective efforts aim to unravel the mysteries of the Universe and gain deeper insights into its fundamental nature.
Our objective is to design, develop and characterize a magnetically-shielded vacuum cell where the background magnetic field and magnetic noise are reduced to extremely low values. We aim to generate large electric fields inside this cell, without compromising the magnetic noise. This calls for careful choices of materials and construction methods and measurements of electric currents at the extreme limits of sensitivity. Finally, we aim to integrate magnetic field probes within the cell for in situ, real-time field measurement and control. The output will be an instrument capable of sensing tiny fields and forces beyond the current state of the art.
One application of such an apparatus in fundamental science is to measure the roundness of the electron, which is measured through its electric dipole moment (eEDM). A non-zero eEDM indicates a violation of time-reversal symmetry, which is crucial in understanding why matter prevails over antimatter in the Universe. To dramatically improve the measurement precision, we have developed transformative techniques to produce trapped ultracold molecules. We have completed a design study of this approach where all the steps are simulated, and have demonstrated most of the key steps with a testbed molecule. The apparatus, which provides precisely controlled magnetic and electric fields, will be the crucial final piece of our new approach, facilitating future experiments to determine electron roundness with unprecedented precision, several hundred times better than before. Such measurements have the potential to discover new particles beyond the reach of particle colliders and shed light on the matter-antimatter asymmetry in the Universe.
Beyond EDM experiments, the apparatus will benefit other tests of fundamental physics using quantum technologies. It will enhance experiments with atom interferometers to probe gravitational waves and ultra-light dark matter, and contribute to atomic clocks to measure varying fundamental constants. The collective efforts aim to unravel the mysteries of the Universe and gain deeper insights into its fundamental nature.
