  Using non-equilibrium molecular dynamics simulations we study the yielding
behaviour of a model cluster crystal formed by ultrasoft particles under shear.
We investigate the evolution of stress as a function of strain for different
shear rates, $\dot{\gamma}$, and temperatures. The stress-strain relation
displays a pronounced maximum at the yielding point; the height of this
maximum, $\sigma_\text{p}$, increases via a power law with an increasing shear
range and tends to saturate to a finite value if the limit shear rate goes to
zero (at least within the considered temperature range). Interestingly, this
behaviour can be captured by the Herschel-Bulkley type model which, for a given
temperature, allows us to predict a static yield stress $\sigma^{0}_\text{p}$
(in the shear rate tending to zero limit), a characteristic timescale
$\tau_\text{c}$, and the exponent $\alpha$ of the above-mentioned power-law
decay of the $\sigma_\text{p}$ at high shear rates. Furthermore, for different
temperatures, the $\sigma_\text{p}$ can be scaled as functions of
$\dot{\gamma}$ onto a single master curve when scaled by corresponding
$\tau_\text{c}$ and ${\sigma}_\text{p}^{0}$. Moreover, for a given shear rate,
$\sigma_\text{p}$ displays a logarithmic dependence on temperature. Again, the
$\sigma_\text{p}{-}T$ curves for different shear rates can be scaled on a
single logarithmic master curve when scaled by a corresponding fitting
parameters.
