Measurement device and method for measuring magnetic resonance signals in a magnetic resonance device and magnetic resonance device

A magnetic resonance (MR) device, comprising:

• at least one measurement device configured to measure MR signals in the MR device, the at least one measurement device including:
• at least one quantum spin magnetometer as a first magnetometer, which includes:
• a sensor material including at least one spin defect center having Zeeman splitting states dependent on an external magnetic field of the MR device,
• an optical excitation source and a microwave excitation source configured to electromagnetically excite the sensor material, and
• a measurement sensor configured to measure optical signals emitted by the excited sensor material and depending on the Zeeman splitting states,
• a second magnetometer associated with the first magnetometer configured to measure a total magnetic field strength of the external magnetic field, which acts as a bias field at the sensor material of the first magnetometer,
• a controller configured to:
• determine a working frequency of the microwave excitation source of the first magnetometer from the total magnetic field strength measured by the second magnetometer, wherein the working frequency is a position of a maximum gradient of the optical signal with respect to the microwave frequency of the microwave excitation source, and
• control the microwave excitation source of the first magnetometer to use the determined working frequency as a microwave frequency, such that the first magnetometer measures the MR signals as the optical signal.

A computer-implemented method for measuring magnetic resonance (MR) signals in a magnetic resonance device using a measurement device having a first magnetometer and a second magnetometer, the method comprising:

• controlling the second magnetometer to measure a current total external magnetic field strength,
• determining a working frequency for a microwave excitation source of the first magnetometer from the total external magnetic field strength measured by the second magnetometer, wherein the working frequency is a position of a maximum gradient of an optical signal with respect to a microwave frequency of the microwave excitation source,
• controlling the microwave excitation source of the first magnetometer to use the determined working frequency as microwave frequency, and
• controlling the first magnetometer to measure the MR signals as the optical signal of a measurement sensor of the first magnetometer.