Given the following context:  Batwoman employs the services of several young female agents known as "Batgirls", in her pursuit of justice. Her archenemy is a masked villain named "Rat Fink". Added to the mix is the President and Vice-President of the "Ayjax Development Corporation". The company, using plutonium as its fuel source, has created a powerful listening device called "The Atomic Hearing Aid", which allows for limitless eavesdropping. The company tried to sell the device to the US Government, but the government wasn't interested due to its unstable power supply. Instead, they ordered the company to destroy the device. The President of Ayjax refused to destroy it, and Rat Fink is pressuring the company to give him the device. The Vice President of Ayjax recruits Batwoman to protect the device, but Rat Fink's minions use drugged bowls of soup to incapacitate Batwoman and her allies and steal the device. The two storm the lair and retrieve it, unmasking Rat Fink and converting one of his minions, Tiger, to the side of justice after he falls in love with one of the Batgirls.  answer the following question:  What is the name of the entity that created a powerful listening device using plutonium?
Ayjax Development Corporation