Are there gels in quantum systems Jrg Schmalian

Are there gels in quantum systems? Jörg Schmalian, Iowa State University and DOE Ames Laboratory Peter G. Wolynes University of California at San Diego Harry Westfahl Jr. LNLS Campinas, Brazil Misha Turlakov Cavendish Laboratory, Cambridge Univ. UK

Classical gels chemical gels irreversible covalent cross -linking (vulcanization) random solid physical gels reversible association of aggregates in copolymers weak crystals and glassy states

Complex aggregates form glassy states Frustrated phase separation in microemusions and copolymers Wu, Westfahl, Schmalian, Wolynes, Chem. Phys. Lett. (2002)) Most systems crystallize easily (under shear), there are glass forming systems S. -H. Chen et al. Science (2003)

A simple model phase A phase B: Phase separation coulomb interaction surfactant mediated interaction new length scale Real space

glassiness and entropy crisis trapped in a complex energy landscape In equilibrium: scan the entire landscape metastable state stripe liquid Loss of entropy exponentially many metastable states: breakdown of thermodynamics ( becomes extensive)

typical liquid configuration deep in the glass state Memory effects

Quantum gels (1): cuprates Our initial motivation: charge order in transition metal oxides Ø NMR: extremely slow relaxation glassiness Ø Glassiness: intrinsic, tied to unconventional properties of cuprates Panagopoulos et al. (2001)) Is there a universal origin for glassiness?

Inhomogeneous spectral features 65 m. V (J. C. Davis et al. Science (2001)) 140 Å High-temperature superconductors 01025 d 02 avg delta 30 m. V 1. 5 n. S 0Å 2 A(- ) 91126153 from A(+ ) typical linecut on Ni BSCCO 0. 7 n. S A( ) 01025 d 02 neg val

Self generated stripe glass J. S. and P. Wolynes Phys. Rev. Lett. 85, 836 (2000); H. Westfahl Jr. , J. S. , and P. G. Wolynes, Phys. Rev. B 64, 174203 (2001); ibid. Intl. J. Mod. Phys. B 15, 3292 (2001) , ibid Phys, Rev. B 68, 134203 (2003) Using: Yamada et al. PRB (1998) Stripe liquid AF SC Stripe glass region 10 (20) times lm contains 6 (106) states

Quantum gels (2): Mn. Si, magnetic rotons (J. S. and M. Turlakov, Phys. Rev. Lett. (2004)) Mn. Si: no-inversion symmetry helical magnet (Ch. Pfleiderer et al. Nature 2001) true non Fermi liquid behavior 2 nd-order transition 1 st-order transition

magnetic rotons: (J. S. and M. Turlakov) dramatic increase in the phase space of magnetic excitations due to helix fluctuations • fluctuation induced 1 st order transition • non-Fermi liquid transport • Amorphous ordering of helices at high pressure (“roton glass”) neutron scattering (C. Pfleiderer et al. Nature (2004) )

relation to Mn. Si ordinary second order transition anomalous transport due to amorphous helical order speculate: anomalous Hall effect

Quantum melting of a stripe glass quantum liquid quantum glass mixed state (at T=0) unique (pure) ground state discontinuous transition Liquid droplet formation and coexistence of liquid and glass at the quantum melting point !

Conclusions Ø Competing interactions in correlated electron systems can lead to non-equilibrium dynamics in quantum systems and glassy behavior not necessarily related to quenched disorder