Effective Dimensionality Change of Fluctuations in Superconductors in a Magnetic Field

In an external magnetic field and near the transition temperature $T_{c2\mathrm{}}\mathrm{}\left(H\right)\mathrm{}$, bulk and thin-film superconductors exhibit an effective change to one- and zero-dimensional behavior in their fluctuation specific heats, which diverge like ${(\frac{T}{T_{c2\mathrm{}}}-1)}^{-\frac{3}{2}}$ and ${(\frac{T}{T_{c2\mathrm{}}}-1)}^{-2\mathrm{}}$, respectively. This enhancement effect is accompanied by a field-dependent broadening of the critical region.