Quantum Sensing of Magnetic Fields Using Global Optimization Algorithms

Experimentally achieving optimal performance of quantum sensors, such as optically pumped magnetometers, is usually challenging and time consuming due to the complexity of the physical system. For a given experiment scheme, there are usually many experiment parameters that need to be fine tuned for achieving a satisfying performance of the quantum sensor. By employing global optimization algorithms, we propose an automatic and efficient way to optimize the sensor performance. We take the most sensitive magnetic field sensor, i.e., the optically pumped magnetometer, as an example to demonstrate how these algorithms facilitate the automatic optimization of quantum sensors. Both the optimization of zero-field magnetometers in a magnetic shield and the finite-field magnetometers in open Earth's field are demonstrated. A noise floor of approximately 10fT/Hz1/2 is achieved within a short time. This method provides an efficient way for quantum sensor optimization and will be helpful for the quantum sensor design.