Color centers in diamond are promising systems for quantum technologies and nanophotonics as they
are photostable emitters at room and elevated temperatures. The possibility of their electrical excitation
has already been demonstrated within p-i-n diodes. However, this requires the growth of complex dia mond structures. In contrast to these conventional approaches, we demonstrate the emission from color
centers under electrical pumping in a Schottky diode configuration based on n-type diamond. Hydrogen
passivation allows the modification of the Schottky barrier height and improves the injection of minority
charge carriers needed for the electrical pumping, while electrons are provided by the n-type layer.