Compensation-dependence of magnetic and electrical properties in $Ga1−xMnxP$

We demonstrate the control of the hole concentration in $Ga1−xMnxP$ over a wide range by introducing compensating vacancies. The resulting evolution of the Curie temperature from 51 to 7.5 K is remarkably similar to that observed in $Ga1−xMnxAs$ despite the dramatically different character of hole transport between the two material systems. The highly localized nature of holes in $Ga1−xMnxP$ is reflected in the accompanying increase in resistivity by many orders of magnitude. Based on variable-temperature resistivity data we present a general picture for hole conduction in which variable-range hopping is the dominant transport mechanism in the presence of compensation.