Continuous order-to-order quantum phase transitions from fixed-point annihilation

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Abstract

A central concept in the theory of phase transitions beyond the Landau-Ginzburg-Wilson paradigm is fractionalization: the formation of new quasiparticles that interact via emergent gauge fields. This concept has been extensively explored in the context of continuous quantum phase transitions between distinct orders that break different symmetries. We propose a mechanism for continuous order-to-order quantum phase transitions that operates independently of fractionalization. This mechanism is based on the collision and annihilation of two renormalization group fixed points: a quantum critical fixed point and an infrared stable fixed point. The annihilation of these fixed points rearranges the flow topology, eliminating the disordered phase associated with the infrared stable fixed point and promoting a second critical fixed point, unaffected by the collision, to a quantum critical point between distinct orders. We argue that this mechanism is relevant to a broad spectrum of physical systems. In particular, it can manifest in Luttinger fermion systems in three spatial dimensions, leading to a continuous quantum phase transition between an antiferromagnetic Weyl semimetal state, which breaks time-reversal symmetry, and a nematic topological insulator, characterized by broken lattice rotational symmetry. This continuous antiferromagnetic-Weyl-to-nematic-insulator transition might be observed in rare-earth pyrochlore iridates R 2 Ir2O7. Other possible realizations include kagome quantum magnets, quantum impurity models, and quantum chromodynamics with supplemental four-fermion interactions.

Details

OriginalspracheEnglisch
Aufsatznummer098001
FachzeitschriftReports on progress in physics
Jahrgang88
Ausgabenummer9
PublikationsstatusVeröffentlicht - 15 Sept. 2025
Peer-Review-StatusJa

Externe IDs

PubMed 40897199

Schlagworte

ASJC Scopus Sachgebiete

Schlagwörter

  • fixed-point annihilation, Luttinger semimetals, nematic topological insulator, pyrochlore iridates, quantum criticality, Weyl semimetal