1. Robinson Research Institute, Victoria University of Wellington, Lower Hutt, New Zealand;2. MacDiarmid Institute for Advanced Materials and Nanotechnology, Lower Hutt, New Zealand;3. MacDiarmid Institute for Advanced Materials and Nanotechnology, Lower Hutt, New ZealandE‐mail:
Abstract:
Recently, compressed H2S has been shown to become superconducting at 203 K under a pressure of 155 GPa. One might expect fluctuations to dominate at such temperatures. Using the magnetisation critical current, we determine the ground‐state London penetration depth, λ0=189 nm, and the superconducting energy gap, Δ0=27.8 meV, and find these parameters are similar to those of cuprate superconductors. We also determine the fluctuation temperature scale, K, which shows that, unlike the cuprates, of the hydride is not limited by fluctuations. This is due to its three dimensionality and suggests the search for better superconductors should refocus on three‐dimensional systems where the inevitable thermal fluctuations are less likely to reduce the observed .
K, which shows that, unlike the cuprates, 
of the hydride is not limited by fluctuations. This is due to its three dimensionality and suggests the search for better superconductors should refocus on three‐dimensional systems where the inevitable thermal fluctuations are less likely to reduce the observed 
. 
