Ballistic avalanche photodiodes: Ultralow noise avalanche diodes with nearly equal ionization probabilities

Avalanche photodiode structures are proposed which theoretically exhibit very low excess noise. In these designs, the hole and electron ionization probabilities are made very close to unity for a single pass of the multiplication region. This is accomplished by ballistic injection across the gain region. The structures are less complex than other proposed low noise avalanche photodiode structures.