Laser scaling for generation of megatesla magnetic fields by microtube implosions

D Shokov,J.J Honrubia,M Murakami

doi:10.1017/hpl.2021.46

Abstract

Microtube implosions are a novel scheme to generate ultrahigh magnetic fields of the megatesla order. These implosions are driven by ultraintense and ultrashort laser pulses. Using two- and three-dimensional particle simulations where megatesla-order magnetic fields can be achieved, we demonstrate scaling and criteria in terms of laser parameters, such as laser intensity and laser energy, to facilitate practical experiments toward the realization of extreme physical conditions, which have yet to be realized in laboratories. Microtube implosions should provide a new platform for studies in fundamental and applied physics relevant to ultrahigh magnetic fields.

Highlights

Magnetic fields are applied in various areas of modern physics and engineering
If τL τH, the absorbed laser energy cannot be effectively transferred to the central core, which is where strong spin currents and strong magnetic fields are generated
We here briefly discuss on a criterion of the seed magnetic field in terms of the target and laser parameters to accomplish the current microtube implosion (MTI) scenario

Summary

Introduction

Magnetic fields are applied in various areas of modern physics and engineering. In the past 50 years, researchers have strived to realize strong magnetic fields in laboratories for fundamental studies and diverse applications [1,2,3,4,5,6,7,8,9]. Irradiating a micron-sized, cylindrically hollow target with relativistically intense laser pulses generates hot electrons (Fig.). The kilotesla-order, uniform, pre-seeded magnetic fields [22, 26,27,28,29,30,31] parallel to the target central axis launch Larmor gyromotions of electrons and ions, deflecting their trajectories in the opposite direction. To clarify the quantitative relation between the achievable magnetic field, applied laser, and target parameters, we avoid the polarity switching regime by assuming a relatively strong seed magnetic field B0 = 6 kT. Circular cross-section microtubes (Fig.1) induce both forward and reverse polarities, depending on several external parameters such as the wall thickness and the strength of the seed magnetic field [38].

Simulation results

Model for laser scaling

Discussion