arXiv subjects

S. Metayer

Publications and source records attributed to S. Metayer.

8 recordsLinked to original sources

arXiv2024

Four-loop elasticity renormalization of low-temperature flat polymerized membranes

We provide the complete four-loop perturbative renormalization of a low-temperature statistical mechanics model of flat polymerized membranes. Using a non-local effective flexural theory, which is based on transverse elastic fluctuations, we analytically determine the anomalous elasticity critical exponent $\eta$, which controls all scaling behaviors in the theory, at the four existing fixed points. The results are obtained as apparently convergent series, allowing for precise estimates without resummations. We independently verify and supplement the results of recent four-loop work [Pikelner 2022 EPL 138 17002] derived from a different model. Additionally, we find good agreement with non-perturbative theoretical approaches and experimental results on soft materials and graphene.

cond-mat.stat-mech↗

arXiv2023

Critical properties of three-dimensional many-flavour QEDs

We review several variants of three-dimensional quantum electrodynamics (QED$_3$) with $N_f$ fermion (or boson) flavors including fermionic (or spinorial) QED$_3$, bosonic (or scalar) QED$_3$, $\mathcal{N}=1$ supersymmetric QED and also models of reduced QED (supersymmetric or not). We begin with an introduction to these models and their flow to a stable infra-red fixed point in the large-$N_f$ limit. We then present detailed state-of-the-art computations of the critical exponents of these models within the dimensional regularization (and reduction) scheme(s), at the next-to-leading order in the $1/N_f$ expansion and in an arbitrary covariant gauge. We finally discuss dynamical (matter) mass generation and the current status of our understanding of the phase structure of these models.

hep-th↗

arXiv2022

Electron mass anomalous dimension at $O(1/N_f^2)$ in three-dimensional $\mathcal{N}=1$ supersymmetric QED

We consider massless three-dimensional $\mathcal{N}=1$ supersymmetric quantum electrodynamics (QED) with $N_f$ flavours of electrons. Within the dimensional reduction scheme, we compute the critical exponents corresponding to both the electron and selectron field and (parity-even) mass anomalous dimensions at the next-to-leading order in the $1/N_f$ expansion and in an arbitrary covariant gauge. The equality of the gauge-invariant mass anomalous dimensions of the electron and the selectron is found to result from a subtle role played by the epsilon-scalars. Our general framework also allows us to compute the critical exponents of pure scalar QED and to recover known results in the case of spinor QED. An application of our results to dynamical (s)electron mass generation is considered. We find evidence that, while dynamical flavor symmetry breaking occurs in spinor QED, both pure scalar QED and supersymmetric QED remain in an interacting conformal phase.

hep-th↗

arXiv2022

Flat polymerized membranes at three-loop order

In this conference report, we present a recent field theoretic renormalization group analysis of flat polymerized membranes at three-loop order by the present authors [Phys. Rev. E 105, L012603 (2022)].

cond-mat.stat-mech↗

arXiv2022

Flat phase of quenched disordered membranes at three-loop order

We study quenched disordered polymerized membranes in their flat phase by means of a three-loop perturbative analysis performed in dimension $D = 4-\epsilon$. We derive the renormalization group equations at this order and solve them up to order $\epsilon^3$. Our results confirm those obtained by Coquand et al. within a nonperturbative approach [Phys. Rev. E 97, 030102(R) (2018)] predicting a finite-temperature, finite-disorder wrinkling transition and those obtained by Coquand and Mouhanna within a recent two-loop order approach [Phys. Rev. E 103, L031001 (2021)], while correcting some of the results obtained in this last reference. We compute the anomalous dimensions that characterize the scaling behavior at the various fixed points of the renormalization group flow diagram. They appear to be in strong agreement with those predicted within the nonperturbative context.

cond-mat.dis-nn↗

arXiv2021

Three-loop order approach to flat polymerized membranes

We derive the three-loop order renormalization group equations that describe the flat phase of polymerized membranes within the modified minimal subtraction scheme, following the pioneering one-loop order computation of Aronovitz and Lubensky [Phys. Rev. Lett. 60, 2634 (1988)] and the recent two-loop order one of Coquand, Mouhanna and Teber [Phys. Rev. E 101, 062104 (2020)]. We analyze the fixed points of these equations and compute the associated field anomalous dimension $\eta$ at three-loop order. Our results display a marked proximity with those obtained using nonperturbative techniques and reexpanded in powers of $\epsilon=4-D$. Moreover, the three-loop order value that we get for $\eta$ at the stable fixed point, $\eta=0.8872$, in $D=2$, is compatible with known theoretical results and within the range of accepted numerical values.

cond-mat.stat-mech↗

arXiv2021

Two-loop mass anomalous dimension in reduced quantum electrodynamics and application to dynamical fermion mass generation

We consider reduced quantum electrodynamics (RQED$_{d_\gamma,d_e}$) a model describing fermions in a $d_e$-dimensional space-time and interacting via the exchange of massless bosons in $d_\gamma$-dimensions ($d_e \leq d_\gamma$). We compute the two-loop mass anomalous dimension, $\gamma_m$, in general RQED$_{4,d_e}$ with applications to RQED$_{4,3}$ and QED$_4$. We then proceed on studying dynamical (parity-even) fermion mass generation in RQED$_{4,d_e}$ by constructing a fully gauge-invariant gap equation for RQED$_{4,d_e}$ with $\gamma_m$ as the only input. This equation allows for a straightforward analytic computation of the gauge-invariant critical coupling constant, $\alpha_c$, which is such that a dynamical mass is generated for $\alpha_r > \alpha_c$, where $\alpha_r$ is the renormalized coupling constant, as well as the gauge-invariant critical number of fermion flavours, $N_c$, which is such that $\alpha_c \rightarrow \infty$ and a dynamical mass is generated for $N < N_c$. For RQED$_{4,3}$, our results are in perfect agreement with the more elaborate analysis based on the resolution of truncated Schwinger-Dyson equations at two-loop order. In the case of QED$_4$, our analytical results (that use state of the art five-loop expression for $\gamma_m$) are in good quantitative agreement with those obtained from numerical approaches.

hep-th↗

arXiv2021

$\mathcal{N}=1$ supersymmetric three-dimensional QED in the large-$N_f$ limit and applications to super-graphene

We study $\mathcal{N}=1$ supersymmetric three-dimensional Quantum Electrodynamics with $N_f$ two-component fermions. Due to the infra-red (IR) softening of the photon, $\ep$-scalar and photino propagators, the theory flows to an interacting fixed point deep in the IR, $p_E \ll e^2 N_f/8$, where $p_E$ is the euclidean momentum and $e$ the electric charge. At next-to-leading order in the $1/N_f$-expansion, we find that the flow of the dimensionless effective coupling constant $\overline{\al}$ is such that: $\overline{\al} \ra 8/\big(N_f \,(1+C/N_f)\big) \approx (8/N_f)(1-0.4317/N_f)$ where $C= 2\,(12-\pi^2)/\pi^2$. Hence, the non-trivial IR fixed point is stable with respect to quantum corrections. Various properties of the theory are explored and related via a mapping to the ones of a $\mathcal{N}=1$ model of super-graphene. In particular, we derive the interaction correction coefficient to the optical conductivity of super-graphene, $C_{\rm sg} = (12-\pi^2)/(2\pi) = 0.3391$, which is six times larger than in the non-supersymmetric case, $C_{\rm g} = (92-9\pi^2)/(18\pi) = 0.0561$.

hep-th↗