Active magneto gyrator: Memory-induced trapped diamagnetism

Area of Science:

• Statistical mechanics
• Soft matter physics
• Active matter physics

Background:

• Charged active particles in thermal baths exhibit complex dynamics.
• Asymmetric potentials and temperature gradients influence particle behavior.
• Magnetic fields introduce Coriolis forces affecting particle trajectories.

Purpose of the Study:

• To analytically explore the dynamics of a charged active particle in a 2D system.
• To investigate the influence of temperature gradients, asymmetric potentials, and magnetic fields on particle behavior.
• To identify conditions for paramagnetic, diamagnetic, and phase coexistence.

Main Methods:

• Analytical exploration of particle dynamics.
• Consideration of a charged particle in two thermal baths at different temperatures.
• Inclusion of an asymmetric harmonic potential and a perpendicular magnetic field.
• Analysis in both equilibrium and non-equilibrium steady states, including viscoelastic media.

Main Results:

• Potential asymmetry and temperature gradient are not solely responsible for gyration in the presence of activity and magnetic field.
• The system transitions between paramagnetic and diamagnetic phases by tuning parameters.
• A trapped diamagnetic phase emerges within a specific activity-memory parameter space, sensitive to temperature gradients and potential asymmetry.
• Magnetic transitions occur through non-magnetic points in non-equilibrium steady states.

Conclusions:

• The interplay of activity, magnetic field, temperature gradient, and potential asymmetry dictates the magnetic behavior of the particle.
• Non-equilibrium conditions allow for magnetic transitions and the emergence of novel phases.
• System parameters can be tuned to achieve zero magnetic moment even outside equilibrium conditions.