Ultimate absolute Hooge parameter for semiconductors and graphene

The temperature dependence of the Hooge parameter alfaH for both n- and p-type InGaAs heterostructures with as-grown non-alloyed ohmic contacts shows good agreement with that estimated from the harmonic coupling model; alfaH is given by aa/lambda, where aa is the lattice constant and lambda is the mean free path of the semiconductor material. Experimental results for several other semiconducting materials normalized by the mobility ratio also verify the validity of the model. We are now able to estimate the Hooge parameter theoretically from only the material parameters, whereas the experimental results are scattered over several orders of magnitude.