Equivalence of Single-Particle and Transport Lifetimes from Hybridization Fluctuations

Abstract

Single band theories of quantum criticality successfully describe a single-particle lifetime with nonFermi liquid temperature dependence. But, they fail to obtain a charge transport rate with the same dependence unless the interaction is assumed to be momentum independent. Here we demonstrate that a quantum critical material, with a long range mode that transmutes electrons between light and heavy bands, exhibits a quasi-linear temperature dependence for both the single-particle and the charge transport lifetimes, despite the strong momentum dependence of the interaction. Introduction.-One of the most fascinating and least understood properties of the non-Fermi liquid state that is obtained by tuning a heavy fermion metal to a quantum critical point is the temperature dependence of its resistivity ρ(T ) ∼ T n with n ≈ 1 [1,2]. This anomalous T -dependence is a rather general phenomenon whose relevance extends beyond the field of heavy fermions. The most well-known example is perhaps the linear-T resistivity observed in the cuprates in their normal phase [3,4]. Strikingly, the same behavior is found close to a metamagnetic phase transition in Sr 3 Ru 2 O 7 [5]. While in heavy fermion metals the behavior is sometimes sub-linear in T [6] and sometimes quasi-linear [7], there is now a large body of experimental data that establishes the universality of the observation of anomalous exponents [8].

Sachdev-Ye-Kitaev Models and Beyond: A Window into Non-Fermi Liquids

“…1b) (Florens and Georges, 2004;Senthil, 2008a,b); see also (Kotliar, 1995), and a Kondo breakdown transition in a heavy Fermi liquid to a fractionalized FL (Fig. 1c) (Burdin et al, 2002;Coleman et al, 2001;Paul et al, 2007Paul et al, , 2008Paul et al, , 2013Schröder et al, 2000;Senthil et al, 2003Senthil et al, , 2004Si et al, 2001Si et al, , 2003. The critical point across both of these transitions also hosts an electronic critical Fermi surface without low-energy Landau quasiparticles (Senthil, 2008a;Senthil et al, 2004).…”

“…A possibility of particular interest is the 'fractionalized Fermi liquid' (FL*) (Burdin et al, 2002;Paramekanti and Vishwanath, 2004;Senthil et al, 2003Senthil et al, , 2004 in which the Fermi surface is 'small' and includes only the volume of the conduction electrons. The spins S i form a spin liquid state with fractionalized excitations, and the fractionalized excitations are required to exist to allow deviation of the Fermi surface volume from the Luttinger value (Bonderson et al, 2016;Else et al, 2021;Paramekanti and Vishwanath, 2004;Senthil et al, 2004); we also note other discussions of FL* and related states (Andrei and Coleman, 1989;Coleman et al, 2005a;Paschen and Si, 2021;Paul et al, 2007Paul et al, , 2008Paul et al, , 2013Pixley et al, 2014;Si, 2010). In the random fully connected model, the S i spins form the SYK spin liquid of Section VI in the large M limit, as we will describe in Section VIII.B.…”

Effective SU(2) theory for the pseudogap state

“…Details are given in Appendix H). The Boltzmann equation for the non-equilibrium electron distribution f k writes 166,167 (125) where e is the elementary charge, E a static electric field and I ei respectively I ee are the electron-impurity respectively electron-electron collision integrals. The electronelectron collision integral is obtained from Fermi's golden rule…”

Scattering mechanisms and electrical transport near an Ising nematic quantum critical point

“…On the theoretical front, several works have studied trasport near a nematic QCP [2][3][4][5], along with many other investigations of transport in different types of quantum critical metals [17][18][19][20][21][22][23][24][25]. However, the general picture remains unclear.…”