Anomalous photovoltaic effect

Anomalous photovoltaic effect is when light shining on some types of materials will produce a flow of electricity. This shouldn't happen since there are normally no electrons in the material and no electric current can flow. However, the material is able to pick up electrons from the light and this is how electricity is made. This effect is called "anomalous" because it is strange and unusual - it doesn't normally happen.