Speaker
Description
Pulsars, i.e. fast rotating neutron stars, exhibit an intriguing phenomenon known as “Glitches”. A glitch refers to a sudden increase of the star rotation frequency, which then eventually relaxes back to its slow-down value. The underlying mechanism governing such a behavior is a big open question in the community. A possible explanation is connected to the stochastic unpinning of quantized vortices residing within the stellar interior [1]. In our work, we use a rotating ultracold supersolid as a simulator for the interior of a pulsar. This mechanism has been numerically investigated by slowing down a rotating superfluid in which vortices are pinned by a suitable external potential [2]. Dipolar supersolids, however, provide a more natural and versatile platform for exploring these dynamics. In the supersolid phase, the spontaneous superfluid density modulation naturally provides the forces for vortex trapping, eliminating the need for artificial pinning sites [3]. By spatially tuning the isotropic interaction strength, we realize a regime where three distinct phases can coexist in the same state: uniform superfluidity, modulated superfluidity, and discrete droplets. This work numerically investigates the vortex dynamics inside this multi-phase environment, mimicking the diverse conditions encountered at different radial depths within a neutron star.
[1] A. Melatos et al., ApJ 672, 1103 (2008).
[2] L. Warszawski and A. Melatos, MNRAS 415, 1611 (2011).
[3] E. Poli et al., Phys. Rev. Lett. 131, 223401 (2023).