Fermion Scattering at a Phase Wave (Abstract)

Jing-Lun Li, Georgios M. Koutentakis, Mateja Hrast +3 more

Abstract Spin mixtures of degenerate fermions are a cornerstone of quantum many-body physics, enabling superfluidity, polarons, and rich spin dynamics through s -wave scattering resonances. Combining them with strong, long-range dipolar interactions provides highly flexible control schemes promising even more exotic quantum phases. Recently, microwave shielding gave access to spin-polarized degenerate samples of dipolar fermionic molecules, where tunable p -wave interactions were enabled by field-linked resonances available only by compromising the shielding (due to experimental limitations). Here, we study the scattering properties of a fermionic dipolar spin mixture and show that a universal s -wave resonance is readily accessible without compromising the shielding. We develop a universal description of the tunable s -wave interaction and weakly bound tetratomic states based on the microwave-field parameters. The s -wave resonance paves the way to stable, controllable and strongly-interacting dipolar spin mixtures of deeply degenerate fermions and supports favorable conditions to reach this regime via evaporative cooling.

Asao Arai

First it is shown in an abstract mathematical framework of supersymmetric quantum theory that, under some conditions for the perturbation, the wave and the scattering operators on bosonic states have some connections with those on fermionic ones. In particular, a unitary equivalence between the two scattering operators is proved. Then, a class of supersymmetric quantum mechanical models on Rn is discussed and the abstract general results are applied to obtain some more explicit results on the supersymmetric potential scattering.

H. Q. Xu

Aurea Rosas Vasconcellos, Roberto Luzzi

Cai-Yun Zhao, Hui-Li Han, Ting-Yun Shi

Abstract We investigate the effects of p-wave interactions on Efimov trimers in systems comprising two identical heavy fermions and a light particle, with mass ratios larger than 13.6. Our focus lies on the Borromean regime where the ground-state trimer exists in the absence of dimers. Using pair-wise Lennard–Jones potentials and concentrating on the L π = 1 − symmetry, we explore the critical value of the interspecies s-wave scattering length a c at which the Borromean state appears in several two-component particle systems. Our exploration encompasses the universal properties of a c and the influence of p-wave fermion–fermion interactions on its value. We find that, in the absence of p-wave fermion–fermion interactions, a c is determined universally by the van der Waals radius and mass ratio. However, the introduction of p-wave fermion–fermion interactions unveiled a departure from this universality. Our calculations show that the critical interspecies scattering length a c now depends on the details of the fermion–fermion p-wave interaction. And, the presence of p-wave fermion–fermion interactions favors the formation of the Borromean state. Additionally, our investigation reveals that Efimov effect in the 1 − symmetry persist even when the fermion–fermion interaction reaches the p-wave unitary limit.