title: Magnetic phase diagram of underdoped YBa2Cu3Oyinferred from torque magnetization and thermal conductivity.
abstract: Strong evidence for charge-density correlation in the underdoped phase of the cuprate YBa2Cu3Oywas obtained by NMR and resonant X-ray scattering. The fluctuations were found to be enhanced in strong magnetic fields. Recently, 3D charge-density-wave (CDW) formation with long-range order (LRO) was observed by X-ray diffraction in [Formula: see text] 15 T. To elucidate how the CDW transition impacts the pair condensate, we have used torque magnetization to 45 T and thermal conductivity [Formula: see text] to construct the magnetic phase diagram in untwinned crystals with hole densityp= 0.11. We show that the 3D CDW transitions appear as sharp features in the susceptibility and [Formula: see text] at the fields [Formula: see text] and [Formula: see text], which define phase boundaries in agreement with spectroscopic techniques. From measurements of the melting field [Formula: see text] of the vortex solid, we obtain evidence for two vortex solid states below 8 K. At 0.5 K, the pair condensate appears to adjust to the 3D CDW by a sharp transition at 24 T between two vortex solids with very different shear moduli. At even higherH(41 T), the second vortex solid melts to a vortex liquid which survives to fields well above 41 T. de Haas-van Alphen oscillations appear at fields 24-28 T, below the lower bound for the upper critical field [Formula: see text].
authors: Department of Physics, University of Michigan, Ann Arbor, MI 48109.
authors: Fan
authors: F
authors: Yu
authors: Department of Physics, Princeton University, Princeton, NJ 08544.
authors: Max
authors: M
authors: Hirschberger
authors: Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany.
authors: Toshinao
authors: T
authors: Loew
authors: Department of Physics, University of Michigan, Ann Arbor, MI 48109.
authors: Gang
authors: G
authors: Li
authors: Department of Physics, University of Michigan, Ann Arbor, MI 48109.
authors: Benjamin J
authors: BJ
authors: Lawson
authors: Department of Physics, University of Michigan, Ann Arbor, MI 48109.
authors: Tomoya
authors: T
authors: Asaba
authors: Department of Physics, Florida State University, Tallahassee, FL 32310.|National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32306.
authors: J B
authors: JB
authors: Kemper
authors: Department of Physics, Princeton University, Princeton, NJ 08544.
authors: Tian
authors: T
authors: Liang
authors: Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany.
authors: Juan
authors: J
authors: Porras
authors: Department of Physics, Florida State University, Tallahassee, FL 32310.|National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32306.
authors: Gregory S
authors: GS
authors: Boebinger
authors: National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545.
authors: John
authors: J
authors: Singleton
authors: Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany.
authors: Bernhard
authors: B
authors: Keimer
authors: Department of Physics, University of Michigan, Ann Arbor, MI 48109.
authors: Lu
authors: L
authors: Li
authors: Department of Physics, Princeton University, Princeton, NJ 08544; npo@princeton.edu.
authors: N Phuan
authors: NP
authors: Ong
keywords: cuprate superconductivity; high-field phase diagram; thermal conductivity; torque magnetometry; vortex liquid