The pseudogap metal phase of hole-doped cuprates can be described by small Fermi surfaces of electronlike quasiparticles, which enclose a volume violating the Luttinger relation. This violation requires the existence of additional fractionalized excitations which can be viewed as fractionalized remnants of the paramagnon. We fractionalize the paramagnon into the bosonic spinons of the spin liquid described by the ${\mathbb{CP}}^{1}$ U(1) gauge theory, and we present a gauge theory of the bosonic spinons, a Higgs field, and an ancilla layer of fermions coupled to the original electrons. Along with the small Fermi surface pseudogap metal, this theory displays conventional phases: the large Fermi surface Fermi liquid with a low-energy paramagnon mode, and phases with spin density wave order. We describe the evolution of the electronic photoemission spectrum across these quantum phase transitions. We consider both the two-sublattice N\'eel and incommensurate spin density wave phases, and we find that the latter has spiral spin correlations.The pseudogap metal phase of hole-doped cuprates can be described by small Fermi surfaces of electronlike quasiparticles, which enclose a volume violating the Luttinger relation. This violation requires the existence of additional fractionalized excitations which can be viewed as fractionalized remnants of the paramagnon. We fractionalize the paramagnon into the bosonic spinons of the spin liquid described by the ${\mathbb{CP}}^{1}$ U(1) gauge theory, and we present a gauge theory of the bosonic spinons, a Higgs field, and an ancilla layer of fermions coupled to the original electrons. Along with the small Fermi surface pseudogap metal, this theory displays conventional phases: the large Fermi surface Fermi liquid with a low-energy paramagnon mode, and phases with spin density wave order. We describe the evolution of the electronic photoemission spectrum across these quantum phase transitions. We consider both the two-sublattice N\'eel and incommensurate spin density wave phases, and we find that the latter has spiral spin correlations.

arXiv:2211.10452Physical review. B./Physical review. BJul 14, 202315 citations

First order phase transitions and perturbation theory

Jean Bricmont, Joseph Slawny

Springer eBooksApr 7, 200816 citations

Nonequilibrium quantum mechanics: A “hot quantum soup” of paramagnons

Harley D. Scammell, Oleg P. Sushkov

Motivated by recent measurements of the lifetime (decay width) of paramagnons in quantum antiferromagnet ${\mathrm{TlCuCl}}_{3}$ , we investigate paramagnon decay in a heat bath and formulate an appropriate quantum theory. Our formulation can be split into two regimes: (i) a nonperturbative, ``hot quantum soup'' regime where the paramagnon width is comparable to its energy; (ii) a usual perturbative regime where the paramagnon width is significantly lower than its energy. Close to the Neel temperature, the paramagnon width becomes comparable to its energy and falls into the hot quantum soup regime. To describe this regime, we develop a new finite frequency, finite temperature technique for a nonlinear quantum field theory; the ``golden rule of quantum kinetics.'' The formulation is generic and applicable to any three-dimensional quantum antiferromagnet in the vicinity of a quantum critical point. Specifically, we apply our results to ${\mathrm{TlCuCl}}_{3}$ and find agreement with experimental data. Additionally, we show that logarithmic running of the coupling constant in the upper critical dimension changes the commonly accepted picture of the quantum disordered and quantum critical regimes.Motivated by recent measurements of the lifetime (decay width) of paramagnons in quantum antiferromagnet ${\mathrm{TlCuCl}}_{3}$, we investigate paramagnon decay in a heat bath and formulate an appropriate quantum theory. Our formulation can be split into two regimes: (i) a nonperturbative, ``hot quantum soup'' regime where the paramagnon width is comparable to its energy; (ii) a usual perturbative regime where the paramagnon width is significantly lower than its energy. Close to the Neel temperature, the paramagnon width becomes comparable to its energy and falls into the hot quantum soup regime. To describe this regime, we develop a new finite frequency, finite temperature technique for a nonlinear quantum field theory; the ``golden rule of quantum kinetics.'' The formulation is generic and applicable to any three-dimensional quantum antiferromagnet in the vicinity of a quantum critical point. Specifically, we apply our results to ${\mathrm{TlCuCl}}_{3}$ and find agreement with experimental data. Additionally, we show that logarithmic running of the coupling constant in the upper critical dimension changes the commonly accepted picture of the quantum disordered and quantum critical regimes.

arXiv:1605.05460Physical review. B./Physical review. BJan 20, 201714 citations

Electronic spectra with paramagnon fractionalization in the single-band Hubbard model

Eric Mascot, Alexander Nikolaenko, Maria Tikhanovskaya +3 more

We examine spectral properties of a recently proposed theory of the intermediate temperature pseudogap metal phase of the cuprates. We show that this theory can be obtained from the familiar paramagnon theory of nearly antiferromagnetic metals by fractionalizing the paramagnon into two ``hidden'' layers of $S=1/2$ spins. The first hidden layer of spins hybridizes with the electrons as in a Kondo lattice heavy Fermi liquid, whereas the second hidden layer of spins forms a spin liquid with fractionalized spinon excitations. We compute the imaginary part of the electronic self-energy induced by the spinon excitations. The energy and momentum dependence of the photoemission spectrum across the Brillouin zone provides a good match to observations by He et al. [Science 331, 1579 (2011)] in $({\mathrm{Pb}}_{x},{\mathrm{Bi}}_{2\ensuremath{-}x})({\mathrm{La}}_{y}{\mathrm{Sr}}_{2\ensuremath{-}y}){\mathrm{CuO}}_{6+\ensuremath{\delta}}$ and by Chen et al. [Science 366, 1099 (2019)] in ${(\mathrm{Bi},\mathrm{Pb})}_{2}{\mathrm{Sr}}_{2}\mathrm{Ca}{\mathrm{Cu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$.We examine spectral properties of a recently proposed theory of the intermediate temperature pseudogap metal phase of the cuprates. We show that this theory can be obtained from the familiar paramagnon theory of nearly antiferromagnetic metals by fractionalizing the paramagnon into two ``hidden'' layers of $S=1/2$ spins. The first hidden layer of spins hybridizes with the electrons as in a Kondo lattice heavy Fermi liquid, whereas the second hidden layer of spins forms a spin liquid with fractionalized spinon excitations. We compute the imaginary part of the electronic self-energy induced by the spinon excitations. The energy and momentum dependence of the photoemission spectrum across the Brillouin zone provides a good match to observations by He et al. [Science 331, 1579 (2011)] in $({\mathrm{Pb}}_{x},{\mathrm{Bi}}_{2\ensuremath{-}x})({\mathrm{La}}_{y}{\mathrm{Sr}}_{2\ensuremath{-}y}){\mathrm{CuO}}_{6+\ensuremath{\delta}}$ and by Chen et al. [Science 366, 1099 (2019)] in ${(\mathrm{Bi},\mathrm{Pb})}_{2}{\mathrm{Sr}}_{2}\mathrm{Ca}{\mathrm{Cu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$.

arXiv:2111.13703Physical review. B./Physical review. BFeb 25, 202220 citations

The Mott transition in the strong coupling perturbation theory

A. Sherman

arXiv:1407.3919Physica B Condensed MatterAug 27, 201412 citations

{\mathbb{CP}}^{1}

U(1) gauge theory, and we present a gauge theory of the bosonic spinons, a Higgs field, and an ancilla layer of fermions coupled to the original electrons. Along with the small Fermi surface pseudogap metal, this theory displays conventional phases: the large Fermi surface Fermi liquid with a low-energy paramagnon mode, and phases with spin density wave order. We describe the evolution of the electronic photoemission spectrum across these quantum phase transitions. We consider both the two-sublattice N\'eel and incommensurate spin density wave phases, and we find that the latter has spiral spin correlations.

Motivated by recent measurements of the lifetime (decay width) of paramagnons in quantum antiferromagnet

{\mathrm{TlCuCl}}_{3}

, we investigate paramagnon decay in a heat bath and formulate an appropriate quantum theory. Our formulation can be split into two regimes: (i) a nonperturbative, ``hot quantum soup'' regime where the paramagnon width is comparable to its energy; (ii) a usual perturbative regime where the paramagnon width is significantly lower than its energy. Close to the Neel temperature, the paramagnon width becomes comparable to its energy and falls into the hot quantum soup regime. To describe this regime, we develop a new finite frequency, finite temperature technique for a nonlinear quantum field theory; the ``golden rule of quantum kinetics.'' The formulation is generic and applicable to any three-dimensional quantum antiferromagnet in the vicinity of a quantum critical point. Specifically, we apply our results to

{\mathrm{TlCuCl}}_{3}

and find agreement with experimental data. Additionally, we show that logarithmic running of the coupling constant in the upper critical dimension changes the commonly accepted picture of the quantum disordered and quantum critical regimes.

S=1/2

spins. The first hidden layer of spins hybridizes with the electrons as in a Kondo lattice heavy Fermi liquid, whereas the second hidden layer of spins forms a spin liquid with fractionalized spinon excitations. We compute the imaginary part of the electronic self-energy induced by the spinon excitations. The energy and momentum dependence of the photoemission spectrum across the Brillouin zone provides a good match to observations by He et al. [Science 331, 1579 (2011)] in $({\mathrm{Pb}}_{x},{\mathrm{Bi}}_{2\ensuremath{-}x})({\mathrm{La}}_{y}{\mathrm{Sr}}_{2\ensuremath{-}y}){\mathrm{CuO}}_{6+\ensuremath{\delta}}$ and by Chen et al. [Science 366, 1099 (2019)] in ${(\mathrm{Bi},\mathrm{Pb})}_{2}{\mathrm{Sr}}_{2}\mathrm{Ca}{\mathrm{Cu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$.