Nuclear magnetic relaxation under high pressure in the spin ladder Sr2Ca12Cu24O41 Original Research Article

Nuclear magnetic resonance (NMR) under pressure below 3 GPa was performed by using a single crystal of Sr2Ca12Cu24O41 to investigate the spin dynamics on the critical regime neighboring the superconducting phase. The temperature dependence of the relaxation rate 1/T1 deviates from an activated type below 50 K and exhibits power law behavior. On the other hand, 1/T1 increases as pressure is increased at low temperatures. These features are intrinsic to this system and reflect some fluctuations originating from holes.