Attractive polaron formed in doped nonchiral/chiral parabolic system within ladder approximation

Abstract

We investigate the properties of attractive polaron formed by a single impurity dressed with the particle-hole excitations in a three-dimensional (3D) doped (extrinsic) parabolic system. %at zero-temperature limit. Base on the single particle-hole variational ansatz, we study the pair propagator, self-energy, and the non-self-consistent medium $T$-matrix. The non-self-consistent $T$-matrix discussed in this paper contains only the open channel since we don't consider the shift of center-of-mass due to the resonance (e.g., induced by the magnetic field). Besides, since we focus on the low-density regime of the majority particles, the effective Fermi wave vector is small. The scattering form factor is discussed in detail for the chiral case and compared to the non-chiral one. The effects of the bare coupling strength, which is momentum-cutoff-dependent, are also discussed. %within the pair propagator due to the scattering %with a certain scattering angle. We found that the pair propagator and the related quantities, like the self-energy, spectral function, induced effective mass, and residue (spectral weight), all exhibit different features in the low-momentum regime and the high one, which also related to the polaronic instabilities as well as the many-body fluctuation and nonadiabatic/adiabatic dynamics. The pair-propagator and the energy relaxation time at finite temperature are also explored.