Light Sensitivity of Diamond Monocrystals

We are investigating the use of diamonds as a low density, radiation-hard sensor for nuclear and particle research. Using a radioactive source, we have studied the response of minimum ionizing particles as a function of voltage, polarity, and time stability. While it is well known that polycrystalline diamond is light-sensitive, little is known about the light sensitivity of single crystal diamond. We will report on our studies of the diamond's electronic response to light and the diamond's internal ``polarization'' effect. We also describe our future plans.