Nuclear quadrupole resonances in compact vapor cells: the crossover from the NMR to the NQR interaction regimes

摘要

We present the first experimental study that maps the transformation ofnuclear quadrupole resonances from the pure nuclear quadrupole regime to thequadrupole-perturbed Zeeman regime. The transformation presents an interestingquantum-mechanical problem, since the quantization axis changes from beingaligned along the axis of the electric-field gradient tensor to being alignedalong the magnetic field. We achieve large nuclear quadrupole shifts for I =3/2 131-Xe by using a 1 mm^3 cubic cell with walls of different materials. Whenthe magnetic and quadrupolar interactions are of comparable size, perturbationtheory is not suitable for calculating the transition energies. Rather than useperturbation theory, we compare our data to theoretical calculations using aLiouvillian approach and find excellent agreement.