643 research outputs found
Spin liquid to spin glass crossover in the random quantum Heisenberg magnet
No full textWe study quantum SU() spins with all-to-all and random Heisenberg exchange interactions of root-mean-square strength . The model has a spin liquid ground state with the spinons obeying the equations of the Sachdev-Ye-Kitaev (SYK) model. Numerical studies of the SU(2) model with spins show spin glass order in the ground state, but also display SYK spin liquid behavior in the intermediate frequency spin spectrum. We employ a expansion to describe the crossover from fractionalized fermionic spinons to a confining spin glass state with weak spin glass order . The SYK spin liquid behavior persists down to a frequency , and for \omega < \omega_\ast, the spectral density is linear in , thus quenching the extensive zero temperature entropy of the spin liquid. The linear spectrum is qualitatively similar to that obtained earlier using bosonic spinons for large . We argue that the extensive SYK spin liquid entropy is transformed as to an extensive complexity of the spin glass state
Spin liquids in insulators and metals
No full textSachdev, Subir. (2019). Spin liquids in insulators and metals. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/203394
Resistivity of Bi films
No full textSachdev, Subir. (2009). Resistivity of Bi films. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/53235
The Spin Density Wave Quantum Phase Transition in Two Dimensional Metals
No full textSachdev, Subir. (2011). The Spin Density Wave Quantum Phase Transition in Two Dimensional Metals. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/119028
Theory of a Planckian Metal
No full textSachdev, Subir. (2019). Theory of a Planckian Metal. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/203651
Z2 fractionalized phases of t-J models
No full textSachdev, Subir. (2018). Z2 fractionalized phases of t-J models. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/197513
Theory of a Planckian metal
No full textSachdev, Subir. (2019). Theory of a Planckian metal. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/203395
Nodal quasiparticles and the onset of spin density wave order in the cuprates
No full textSachdev, Subir. (2012). Nodal quasiparticles and the onset of spin density wave order in the cuprates. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/129660
Recommended from our members
Subir Sachdev: publications not on arXiv.org
No full textPhysicsAuthor's Origina
Underdoped cuprates as fractionalized Fermi liquids: Transition to superconductivity
No full textWe model the underdoped cuprates using fermions moving in a background with local antiferromagnetic order. The antiferromagnetic order fluctuates in orientation, but not in magnitude, so that there is no long-range antiferromagnetism, but a "topological" order survives. The normal state is described as a fractionalized Fermi liquid (FL*), with electronlike quasiparticles coupled to the fractionalized excitations of the fluctuating antiferromagnet. The electronic quasiparticles reside near pocket Fermi surfaces enclosing total area x (the dopant density), centered away from the magnetic Brillouin zone boundary. The violation of the conventional Luttinger theorem is linked to a "species doubling" of these quasiparticles. We describe phenomenological theories of the pairing of these quasiparticles, and show that a large class of mean-field theories generically displays a nodal-antinodal "dichotomy": The interplay of local antiferromagnetism and pairing leads to a small gap near the nodes of the d-wave pairing along the Brillouin zone diagonals, and a large gap in the antinodal region
- …
