An x-ray imaging system includes a detector positioned to receive x-rays, an x-ray tube configured to generate x-rays toward the detector from a focal spot surface, the x-ray tube includes a target having the focal spot surface, a cathode support arm, and a cathode attached to the cathode support arm. The cathode includes a split cathode cup having a first portion and a second portion that is separate from the first portion, the first and second portions having respective first and second emitter attachment surfaces, and a flat emitter that is attached to the first and second emitter attachment surfaces such that, when an electrical current is provided to the first portion of the cathode cup, the current passes through the flat emitter and returns through the second portion of the cathode cup such that electrons emit from the flat emitter and toward the focal spot surface.