Anomalous magnetization of a carbon nanotube as an excitonic insulator
arXiv:1405.3108 · doi:10.1103/PhysRevB.90.195415
Abstract
We show theoretically that an undoped carbon nanotube might be an excitonic insulator---the long-sought phase of matter proposed by Keldysh, Kohn and others fifty years ago. We predict that the condensation of triplet excitons, driven by intervalley exchange interaction, spontaneously occurs at equilibrium if the tube radius is sufficiently small. The signatures of exciton condensation are its sizeable contributions to both the energy gap and the magnetic moment per electron. The increase of the gap might have already been measured, albeit with a different explanation [Deshpande et al., Science 323, 106 (2009)]. The enhancement of the quasiparticle magnetic moment is a pair-breaking effect that counteracts the weak paramagnetism of the ground-state condensate of excitons. This property could rationalize the anomalous magnitude of magnetic moments recently observed in different devices close to charge neutrality.
arXiv commentMajor revision with new results and largely expanded discussion of experimental literature
References in corpus (35)
- Luttinger Liquid Behavior in Carbon Nanotubes
- Size, Shape and Low Energy Electronic Structure of Carbon Nanotubes
- Spin-orbit coupling in curved graphene, fullerenes, nanotubes, and nanotube caps
- Excitonic Effects and Optical Spectra of Single-Walled Carbon Nanotubes
- Coulomb Interactions and Mesoscopic Effects in Carbon Nanotubes
- Coupling of Spin and Orbital Motion of Electrons in Carbon Nanotubes
- Effective low-energy theory for correlated carbon nanotubes
- Exciton binding energies in carbon nanotubes from two-photon photoluminescence
- Electron-electron interaction effects on optical excitations in semiconducting single-walled carbon nanotubes
- The Coulomb impurity problem in graphene
- Vacuum Polarization and Screening of Supercritical Impurities in Graphene
- Observing Atomic Collapse Resonances in Artificial Nuclei on Graphene
- Atomic Collapse and Quasi-Rydberg States in Graphene
- Measuring electron orbital magnetic moments in carbon nanotubes
- Electron Transport in Very Clean, As-Grown Suspended Carbon Nanotubes
- Correlation Effects in Carbon Nanotubes
- Relaxation and Dephasing in a Two-electron 13C Nanotube Double Quantum Dot
- Large spin-orbit coupling in carbon nanotubes
- Low Energy Properties of the (n,n) Carbon Nanotubes
- Magnetic Brightening of Carbon Nanotube Photoluminescence through Symmetry Breaking
- Observation and Spectroscopy of a Two-Electron Wigner Molecule in an Ultra-Clean Carbon Nanotube
- Excitons in Carbon Nanotubes with Broken Time-Reversal Symmetry
- Curvature-enhanced spin-orbit coupling in a carbon nanotube
- Electronic Transport Spectroscopy of Carbon Nanotubes in a Magnetic Field
- Carbon nanotubes in electric and magnetic fields
- Carbon nanotubes for coherent spintronic devices
- Excitons in narrow-gap carbon nanotubes
- Narrow gap Luttinger liquid in Carbon nanotubes
- Spin-orbit interaction in chiral carbon nanotubes probed in pulsed magnetic fields
- Interplay of Kondo effect and strong spin-orbit coupling in multi-hole ultraclean carbon nanotubes
- Spectral function of few electrons in quantum wires and carbon nanotubes as a signature of Wigner localization
- Coulomb Blockade Regime of a Single-Wall Nanotube
- Inter-valley scattering induced by Coulomb interaction and disorder in carbon-nanotube quantum dots
- Theory of Ferromagnetism in Doped Excitonic Condensates
- Exciton Hierarchies in Gapped Carbon Nanotubes
Cited by in corpus (9)
- Quantum transport in carbon nanotubes
- Carbon nanotubes as excitonic insulators
- Transport across a carbon nanotube quantum dot contacted with ferromagnetic leads: experiment and non-perturbative modeling
- Topological transitions and fractional charges induced by strain and magnetic field in carbon nanotubes
- Can freestanding Xene monolayers behave as excitonic insulators?
- Exciton-Peierls mechanism and universal many-body gaps in carbon nanotubes
- Coherent exciton transport in semiconductors
- Interaction-driven giant orbital magnetic moments in carbon nanotubes
- Correlated insulating states in carbon nanotubes controlled by magnetic field