@article{8602,
  abstract     = {Collective cell migration offers a rich field of study for non-equilibrium physics and cellular biology, revealing phenomena such as glassy dynamics, pattern formation and active turbulence. However, how mechanical and chemical signalling are integrated at the cellular level to give rise to such collective behaviours remains unclear. We address this by focusing on the highly conserved phenomenon of spatiotemporal waves of density and extracellular signal-regulated kinase (ERK) activation, which appear both in vitro and in vivo during collective cell migration and wound healing. First, we propose a biophysical theory, backed by mechanical and optogenetic perturbation experiments, showing that patterns can be quantitatively explained by a mechanochemical coupling between active cellular tensions and the mechanosensitive ERK pathway. Next, we demonstrate how this biophysical mechanism can robustly induce long-ranged order and migration in a desired orientation, and we determine the theoretically optimal wavelength and period for inducing maximal migration towards free edges, which fits well with experimentally observed dynamics. We thereby provide a bridge between the biophysical origin of spatiotemporal instabilities and the design principles of robust and efficient long-ranged migration.},
  author       = {Boocock, Daniel R and Hino, Naoya and Ruzickova, Natalia and Hirashima, Tsuyoshi and Hannezo, Edouard B},
  issn         = {17452481},
  journal      = {Nature Physics},
  pages        = {267--274},
  publisher    = {Springer Nature},
  title        = {{Theory of mechanochemical patterning and optimal migration in cell monolayers}},
  doi          = {10.1038/s41567-020-01037-7},
  volume       = {17},
  year         = {2021},
}

@article{8673,
  abstract     = {In RuCl3, inelastic neutron scattering and Raman spectroscopy reveal a continuum of non-spin-wave excitations that persists to high temperature, suggesting the presence of a spin liquid state on a honeycomb lattice. In the context of the Kitaev model, finite magnetic fields introduce interactions between the elementary excitations, and thus the effects of high magnetic fields that are comparable to the spin-exchange energy scale must be explored. Here, we report measurements of the magnetotropic coefficient—the thermodynamic coefficient associated with magnetic anisotropy—over a wide range of magnetic fields and temperatures. We find that magnetic field and temperature compete to determine the magnetic response in a way that is independent of the large intrinsic exchange-interaction energy. This emergent scale-invariant magnetic anisotropy provides evidence for a high degree of exchange frustration that favours the formation of a spin liquid state in RuCl3.},
  author       = {Modic, Kimberly A and McDonald, Ross D. and Ruff, J.P.C. and Bachmann, Maja D. and Lai, You and Palmstrom, Johanna C. and Graf, David and Chan, Mun K. and Balakirev, F.F. and Betts, J.B. and Boebinger, G.S. and Schmidt, Marcus and Lawler, Michael J. and Sokolov, D.A. and Moll, Philip J.W. and Ramshaw, B.J. and Shekhter, Arkady},
  issn         = {17452481},
  journal      = {Nature Physics},
  pages        = {240--244},
  publisher    = {Springer Nature},
  title        = {{Scale-invariant magnetic anisotropy in RuCl3 at high magnetic fields}},
  doi          = {10.1038/s41567-020-1028-0},
  volume       = {17},
  year         = {2021},
}

@article{7942,
  abstract     = {An understanding of the missing antinodal electronic excitations in the pseudogap state is essential for uncovering the physics of the underdoped cuprate high-temperature superconductors1,2,3,4,5,6. The majority of high-temperature experiments performed thus far, however, have been unable to discern whether the antinodal states are rendered unobservable due to their damping or whether they vanish due to their gapping7,8,9,10,11,12,13,14,15,16,17,18. Here, we distinguish between these two scenarios by using quantum oscillations to examine whether the small Fermi surface pocket, found to occupy only 2% of the Brillouin zone in the underdoped cuprates19,20,21,22,23,24, exists in isolation against a majority of completely gapped density of states spanning the antinodes, or whether it is thermodynamically coupled to a background of ungapped antinodal states. We find that quantum oscillations associated with the small Fermi surface pocket exhibit a signature sawtooth waveform characteristic of an isolated two-dimensional Fermi surface pocket25,26,27,28,29,30,31,32. This finding reveals that the antinodal states are destroyed by a hard gap that extends over the majority of the Brillouin zone, placing strong constraints on a drastic underlying origin of quasiparticle disappearance over almost the entire Brillouin zone in the pseudogap regime7,8,9,10,11,12,13,14,15,16,17,18.},
  author       = {Hartstein, Máté and Hsu, Yu Te and Modic, Kimberly A and Porras, Juan and Loew, Toshinao and Tacon, Matthieu Le and Zuo, Huakun and Wang, Jinhua and Zhu, Zengwei and Chan, Mun K. and Mcdonald, Ross D. and Lonzarich, Gilbert G. and Keimer, Bernhard and Sebastian, Suchitra E. and Harrison, Neil},
  issn         = {17452481},
  journal      = {Nature Physics},
  pages        = {841--847},
  publisher    = {Springer Nature},
  title        = {{Hard antinodal gap revealed by quantum oscillations in the pseudogap regime of underdoped high-Tc superconductors}},
  doi          = {10.1038/s41567-020-0910-0},
  volume       = {16},
  year         = {2020},
}