How many quantum phase transitions exist inside the superconducting dome of the iron pnictides?

Abstract

Recent experiments on two iron-pnictide families suggest the existence of a single quantum phase transition (QPT) inside the superconducting dome despite the fact that two separate transition lines - magnetic and nematic - cross the superconducting dome at $T_c$. Here we argue that these two observations are actually consistent. We show, using a microscopic model, that each order coexists with superconductivity for a wide range of parameters, and both transition lines continue into the superconducting dome below $T_c$. However, at some $T_{\mathrm{merge}}<T_c$, the two transitions merge and continue down to T=0 as a single simultaneous first-order nematic/magnetic transition. We show that superconductivity has a profound effect on the character of this first-order transition, rendering it weakly first-order and allowing strong fluctuations to exist near the QPT.

revised version; 4 pages + supplementary material

References in corpus (16)

• Fermi-liquid instabilities at magnetic quantum phase transitions
• High-temperature superconductivity in iron-based materials
• To What Extent Iron-Pnictide New Superconductors Have Been Clarified: A Progress Report
• Theory of Electron Nematic Order in LaOFeAs
• Ising and Spin orders in Iron-based Superconductors
• Quantum phase transitions of metals in two spatial dimensions: II. Spin density wave order
• A Sharp Peak of the Zero-Temperature Penetration Depth at Optimal Composition in BaFe2(As1-xPx)2
• Superconductivity and spin-density-waves in multi-band metals
• Interplay between magnetism and superconductivity in Fe-pnictides
• Homogeneous vs. inhomogeneous coexistence of magnetic order and superconductivity probed by NMR in Co and K doped iron pnictides
• Doping evolution of the absolute value of the London penetration depth and superfluid density in single crystals of Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• The role of striction at magnetic and structural transitions in iron-pnictides
• Thermodynamic phase diagram and phase competition in BaFe2(As1-xPx)2 studied by thermal expansion
• Quantum critical point shifts under superconductivity: the pnictides and the cuprates
• Anomalous superfluid density in quantum critical superconductors
• Magnetic penetration depth in the presence of a spin-density wave in multiband superconductors at zero temperature

Cited by in corpus (35)

• Nematic order in iron superconductors - who is in the driver's seat?
• Charge-density-wave order with momentum $(2Q,0)$ and $(0,2Q)$ within the spin-fermion model: continuous and discrete symmetry breaking, preemptive composite order, and relation to pseudogap in hole-doped cuprates
• Intertwined vestigial order in quantum materials: nematicity and beyond
• Nematicity as a probe of superconducting pairing in iron-based superconductors
• Charge Nematicity and Electronic Raman Scattering in Iron-based Superconductors
• Critical Quadrupole Fluctuations and Collective Modes in Iron Pnictide Superconductors
• Pair-Density-Wave Superconducting States and Electronic Liquid Crystal Phases
• Nematic resonance in the Raman response of iron-based superconductors
• Local characterization of superconductivity in BaFe2(As1-xPx)2
• Competition between superconductivity and magnetic/nematic order as a source of anisotropic superconducting gap in underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Quantum phase transition inside the superconducting dome of Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ probed by optical magneto-sensing using NV-centers in diamond
• Phase transition beneath the superconducting dome in BaFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$
• Nematicity and superconductivity: Competition versus cooperation
• Global phase diagram of a spin-orbital Kondo impurity model and the suppression of Fermi-liquid scale
• Order parameter fluctuation and ordering competition in $\mathrm{B}{\mathrm{a}}_{1-\mathrm{x}}{\mathrm{K}}_{\mathrm{x}}\mathrm{F}{\mathrm{e}}_2\mathrm{A}{\mathrm{s}}_2$
• Cascade of vestigial orders in two-component superconductors: nematic, ferromagnetic, s-wave charge-4e, and d-wave charge-4e states
• Direct visualization of phase separation between superconducting and nematic domains in Co-doped CaFe2As2 close to a first order phase transition
• Separation of antiferromagnetism and high-temperature superconductivity in Ca${}_{1-x}$La${}_x$Fe${}_2$As${}_2$ under pressure
• Electronic Nematicity Revealed by Torque Magnetometry in Iron Arsenide EuFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$
• Thermodynamic signatures of an antiferromagnetic quantum critical point inside a superconducting dome
• Effect of SDW fluctuations on the specific heat jump in iron pnictides at a superconducting transition
• Anomalous thermodynamic properties of quantum critical superconductors
• Diamagnetic Vortex Barrier Stripes in Underdoped $BaF{e}_2(A{s}_{1-x}{P}_x{)}_2$
• Impact of ordering competition on the global phase diagram of iron pnictides
• Renormalization group analysis of competition between distinct order parameters
• Competing superconducting and magnetic order parameters and field-induced magnetism in electron doped Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Dependence of the absolute value of the penetration depth in $(\mathbf{B}{\mathbf{a}}_{1-\mathbf{x}}{\mathbf{K}}_{\mathbf{x}})\mathbf{F}{\mathbf{e}}_2\mathbf{A}{\mathbf{s}}_2$ on doping
• Nonlinear uniaxial pressure dependence of $T_c$ in iron-based superconductors
• Magnetic and Ising quantum phase transitions in a model for isoelectronically tuned iron pnictides
• Nematicity, magnetic fluctuation and ferro-spin-orbital ordering in BaFe${}_2$As${}_2$ family
• Anomalous sharp peak in the London penetration depth induced by the nodeless-to-nodal superconducting transition in BaFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$
• Incommensurate magnetic states induced by ordering competition in $\mathrm{B}{\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}{\mathrm{a}}_{\mathrm{x}}\mathrm{F}{\mathrm{e}}_2\mathrm{A}{\mathrm{s}}_2$
• Josephsonic diagnostic of competing orders in quantum critical multiband superconductors
• Universality and unconventional enhancement of flux-flow resistivity in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Relationship between critical current and flux-flow resistivity in the mixed state of Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$