Spectra of heavy polarons and molecules coupled to a Fermi sea | |
Article | |
关键词: X-RAY-ABSORPTION; SINGULARITIES; EMISSION; METALS; SCATTERING; PARTICLE; | |
DOI : 10.1103/PhysRevB.98.220302 | |
来源: SCIE |
【 摘 要 】
We study the spectrum of an impurity coupled to a Fermi sea (e.g., minority atom in an ultracold gas, exciton in a solid) by attraction strong enough to form a molecule/trion. We introduce a diagrammatic scheme which allows treating a finite mass impurity while reproducing the Fermi-edge singularity in the immobile limit. For large binding energies the spectrum is characterized by a semicoherent repulsive polaron and an incoherent molecule-hole continuum, which is the lowest-energy feature in the single-particle spectrum. The previously predicted attractive polaron seems not to exist for strong binding.
【 授权许可】
Free