Which process increases the potential energy of the particles of a sample

Vaporization.

Explanation:

When we heat or raise the energy of any sample, it evaporates. Evaporation is known as a form of Vaporization. When some sample evaporates, then they basically take in heat and when the sample condenses, it cools down by giving out the heat into the surrounding, atmosphere and the energy goes into the atmosphere.

An example of evaporation is the rain cycle. Where it's cooler, water on earth's surface evaporates and travels up through the atmosphere. The cool temperature causing the vapor to condense and back into water drops. When the cloud becomes saturated, the droplets fall to the ground in the form of rain.