Interaxial time-domain interference in single-beam SERF magnetometer

Gradient phase and amplitude errors in atomic magnetic gradiometers for biomagnetic imaging systems

“… 34 Since the magnetic field compensation along the pump axis ( ) is the most error-prone and contributes the most to measurement errors, 1 we only consider the effect of the bias field . Assuming that the angle between the external field to be measured and the sensitive axis ( x -axis) is , the spin polarization along the pumping beam ( ) can be expressed as: 35 where is the atomic Larmor precession rate in the external magnetic field and . For simplify, we use to represent , where denotes the n th order Bessel functions of the first kind.…”

“…Previous studies have systematically discussed the deterministic measurement error that arises from the interaxial response interference of a single-beam modulated SERF magnetometer. 35 In this study, we focus on the measurement error arising from the collective effect of the magnitude distortion exhibited in each OPM in the gradient configuration, which is referred to as the gradient amplitude error. Note that is only related to the frequency of the external magnetic field and the relaxation rate of the atomic ensemble.…”

“…The potential measurement error induced by interference was also demonstrated in an MCG simulation. 35 However, these studies did not consider measurement errors in the OPM gradiometer configuration. The measurement error analysis of magnetic gradiometers is not identical to that of a single magnetometer.…”