Spin-charge split pairing in underdoped cuprate superconductors: support from low- $T$ specific heatSpin-charge split pairing in underdoped cuprate superconductors: support from low-$T$ specific heat

Sanjoy Kumar Sarker, Timothy Lovorn

We calculate the specific heat of a weakly interacting dilute system of bosons on a lattice and show that it is consistent with the measured electronic specific heat in the superconducting state of underdoped cuprates with boson concentration $ρ\sim x/2$ , where $x$ is the hole (dopant) concentration. As usual, the $T^3$ term is due to Goldstone phonons. The zero-point energy, through its dependence on the condensate density $ρ_0(T)$ , accounts for the anomalous $T$ -linear term. These results support the split-pairing mechanism, in which spinons (pure spin) are paired at $T^*$ and holons (pure charge) form real-space pairs at $T_p < T^*$ , creating a gauge-coupled physical pair of charge $+2e$ and concentration $x/2$ which Bose condenses below $T_c$ , accounting for the observed phases.We calculate the specific heat of a weakly interacting dilute system of bosons on a lattice and show that it is consistent with the measured electronic specific heat in the superconducting state of underdoped cuprates with boson concentration $ρ\sim x/2$, where $x$ is the hole (dopant) concentration. As usual, the $T^3$ term is due to Goldstone phonons. The zero-point energy, through its dependence on the condensate density $ρ_0(T)$, accounts for the anomalous $T$-linear term. These results support the split-pairing mechanism, in which spinons (pure spin) are paired at $T^*$ and holons (pure charge) form real-space pairs at $T_p < T^*$, creating a gauge-coupled physical pair of charge $+2e$ and concentration $x/2$ which Bose condenses below $T_c$, accounting for the observed phases.

arXiv:1705.10390May 29, 20170 citations

Entanglement area law from specific heat capacity

Fernando G. S. L. Brandão, M. Cramer

We study the scaling of entanglement in low-energy states of quantum many-body models on lattices of arbitrary dimensions. We allow for unbounded Hamiltonians such that systems with bosonic degrees of freedom are included. We show that, if at low enough temperatures the specific heat capacity of the model decays exponentially with inverse temperature, the entanglement in every low-energy state satisfies an area law (with a logarithmic correction). This behavior of the heat capacity is typically observed in gapped systems. Assuming merely that the low-temperature specific heat decays polynomially with temperature, we find a subvolume scaling of entanglement. Our results give experimentally verifiable conditions for area laws, show that they are a generic property of low-energy states of matter, and constitute proof of an area law for unbounded Hamiltonians beyond those that are integrable.We study the scaling of entanglement in low-energy states of quantum many-body models on lattices of arbitrary dimensions. We allow for unbounded Hamiltonians such that systems with bosonic degrees of freedom are included. We show that, if at low enough temperatures the specific heat capacity of the model decays exponentially with inverse temperature, the entanglement in every low-energy state satisfies an area law (with a logarithmic correction). This behavior of the heat capacity is typically observed in gapped systems. Assuming merely that the low-temperature specific heat decays polynomially with temperature, we find a subvolume scaling of entanglement. Our results give experimentally verifiable conditions for area laws, show that they are a generic property of low-energy states of matter, and constitute proof of an area law for unbounded Hamiltonians beyond those that are integrable.

arXiv:1409.5946Physical Review BSep 16, 201529 citations

Critical Properties of Strongly Interacting Bosons on a Lattice

G. G. Batrouni

Springer proceedings in physicsJan 1, 19930 citations

Double-peak specific heat anomaly and correlations in the Bose-Hubbard model

Eduardo O. Rizzatti, Marco Aurélio A. Barbosa, Márcia C. Barbosa

Considering the thermodynamics of bosons in a lattice described by the Bose-Hubbard Hamiltonian, we report the occurrence of anomalous double peaks in their specific heat dependence on temperature. This feature, usually associated with a high geometrical frustration, can also be a consequence of a purely energetic competition. By employing self-energy functional calculations combined with finite-temperature perturbation theory, we propose a mechanism based on ground-state degeneracies expressed as residual entropies. A general decomposition of the specific heat regarding all possible transitions between the system's eingenvalues provides an insight into the nature of each maximum. Furthermore, we address how the model parameters modify the structure of these peaks based on its spectral properties and atom-atom correlation function.Considering the thermodynamics of bosons in a lattice described by the Bose-Hubbard Hamiltonian, we report the occurrence of anomalous double peaks in their specific heat dependence on temperature. This feature, usually associated with a high geometrical frustration, can also be a consequence of a purely energetic competition. By employing self-energy functional calculations combined with finite-temperature perturbation theory, we propose a mechanism based on ground-state degeneracies expressed as residual entropies. A general decomposition of the specific heat regarding all possible transitions between the system's eingenvalues provides an insight into the nature of each maximum. Furthermore, we address how the model parameters modify the structure of these peaks based on its spectral properties and atom-atom correlation function.

arXiv:2010.06560Oct 13, 20205 citations

Spin-charge split pairing in underdoped cuprate superconductors: support from low-

T

specific heat

ρ\sim x/2

, where

x

is the hole (dopant) concentration. As usual, the

T^3

term is due to Goldstone phonons. The zero-point energy, through its dependence on the condensate density

ρ_0(T)

, accounts for the anomalous

T

-linear term. These results support the split-pairing mechanism, in which spinons (pure spin) are paired at

T^*

and holons (pure charge) form real-space pairs at

T_p < T^*

, creating a gauge-coupled physical pair of charge

+2e

and concentration

x/2

which Bose condenses below

T_c

, accounting for the observed phases.