Dynamical control of nuclear isomer depletion via electron vortex beams

TL;DR

This paper proposes a novel method to control nuclear isomer decay using specially designed electron vortex beams, significantly enhancing energy release from long-lived nuclear states for potential energy applications.

Contribution

It introduces a protocol employing tailored electron vortex beams to externally control nuclear isomer depletion, achieving four to six orders of magnitude increase in decay rates.

Findings

Electron vortex beams increase depletion by four orders of magnitude.

Specific orbitals can enhance recombination cross sections by six orders.

Potential for controlled energy release from nuclear isomers.

Abstract

Long-lived excited states of atomic nuclei can act as energy traps. These states, known as nuclear isomers, can store a large amount of energy over long periods of time, with a very high energy-to-mass ratio. Under natural conditions, the trapped energy is only slowly released, limited by the long isomer lifetimes. Dynamical external control of nuclear state population has proven so far very challenging, despite ground-breaking incentives for a clean and efficient energy storage solution. Here, we describe a protocol to achieve the external control of the isomeric nuclear decay by using electrons whose wavefunction has been especially designed and reshaped on demand. Recombination of these electrons into the atomic shell around the isomer can lead to the controlled release of the stored nuclear energy. On the example of $^{93m}$Mo, we show that the use of tailored electron vortex beams increases the depletion by four orders of magnitude compared to the spontaneous nuclear decay of the isomer. Furthermore, specific orbitals can sustain an enhancement of the recombination cross section for vortex electron beams by as much as six orders of magnitude, providing a handle for manipulating the capture mechanism. These findings open new prospects for controlling the interplay between atomic and nuclear degrees of freedom, with potential energy-related and high-energy radiation sources applications.