Regensburg 2016 – wissenschaftliches Programm
TT 35.6: Vortrag
Dienstag, 8. März 2016, 15:15–15:30, H21
Dimensionless ratios: characteristics of quantum liquids and their phase transitions — Yi-Cong Yu1, Yang-Yang Chen1, Hai-Qing Lin2, •Rudolf A. Römer3, and Xi-Wen Guan1,4,5 — 1Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China — 2Beijing Computational Science Research Center, Beijing 100094, China — 3University of Warwick, Coventry, CV4 7AL, UK — 4Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China — 5Australian National University, Canberra ACT 0200, Australia
Dimensionless ratios of physical properties can be constant in low-temperatures phases in a wide variety of materials. As such, the Wilson ratio (WR), the Kadowaki-Woods ratio and the Wiedemann-Franz law capture essential features of Fermi liquids in metals, heavy fermions, etc. Here we prove that the phases of many-body interacting multi-component quantum liquids in one dimension can be described by WRs based on the compressibility, susceptibility and specific heat associated with each component. These WRs arise due to surprisingly simple additivity rules within subsystems reminiscent of the rules for multi-resistor networks in series and parallel. Using experimentally realized multi-species cold atomic gases as examples, we prove that the Wilson ratios uniquely identify phases of Tomonaga-Luttinger liquids, while providing universal scaling relations at the boundaries between phases. Their values within a phase identify the internal degrees of freedom of said phase such as its spin-degeneracy.