Simultaneous pi/2 rotation of two spin species of different gyromagnetic ratios

TL;DR

This paper analyzes the conditions for simultaneously achieving pi/2 rotations of two different spin species using magnetic pulses, with applications to neutron electric dipole moment experiments.

Contribution

It derives the relationships between pulse parameters and gyromagnetic ratios for simultaneous pi/2 rotations, including numerical solutions and practical application insights.

Findings

Derived equations for rotating magnetic field pulses

Numerical solutions for linear oscillatory fields

Application to neutron and 3He spin manipulation

Abstract

We examine the characteristics of the pi/2 pulse for simultaneously rotating two spin species of different gyromagnetic ratios with the same sign. For a pi/2 pulse using a rotating magnetic field, we derive the equation relating the frequency and strength of the pulse to the gyromagnetic ratios of the two particles and the strength of the constant holding field. For a pi/2 pulse using a linear oscillatory magnetic field, we obtain the solutions numerically, and compare them with the solutions for the rotating pi/2 pulse. Application of this analysis to the specific case of rotating neutrons and 3He atoms simultaneously with a pi/2 pulse, proposed for a neutron electric dipole moment experiment, is also presented.