Magnetic penetration depth and specific heat of the paired-boson superconductor

The mean-field temperature ($T$) dependence of the magnetic penetration depth $\lambda \mathrm{}\left(T\right)\mathrm{}$ of the paired-boson (holon) superconductor is calculated in the London limit. It is found that the dependence of $\frac{\lambda \mathrm{}\left(T\right)\mathrm{}}{\lambda \mathrm{}\left(0\right)\mathrm{}}$ on $\frac{T}{T_c}$ is almost a universal function, and is in good agreement with that observed by Cooper et al. for $\mathrm{Y}{\mathrm{Ba}}_2{\mathrm{Cu}}_3{\mathrm{O}}_{7-\delta }$. It is also stressed that the specific heat, $C_v\mathrm{}\left(T\right)\mathrm{}$, of the holon superconductor is linear in $T$ for all but the lowest temperatures ($T\ll T_c$).