Strong diamagnetic response and specific heat anomaly aboveTcin underdopedLa2−xSrxCuO4

  title={Strong diamagnetic response and specific heat anomaly aboveTcin underdopedLa2−xSrxCuO4},
  author={Ulrik Thisted and J{\o}rgen Nyhus and T. Suzuki and Junya Hori and Kristian Fossheim},
  journal={Physical Review B},
By measuring ac susceptibility using a very low amplitude of the ac field $(l1\mathrm{mG})$ it is shown that underdoped samples of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ are diamagnetic in a temperature region above ${T}_{c}$ up to a temperature ${T}^{*}.$ This behavior is only observed with ac fields along the c axis whereas for fields in the $\mathrm{ab}$ plane no diamagnetism above ${T}_{c}$ was detected. The diamagnetism is almost frequency independent in the… 
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