How does the refrigeration cycle in a heat pump work to transfer heat from a lower temperature source to a higher temperature sink?

The refrigeration cycle in a heat pump works by using a refrigerant to absorb heat from a lower temperature source, such as the air outside, and then transferring that heat to a higher temperature sink, such as the inside of a building. This process is achieved through the use of a compressor, condenser, expansion valve, and evaporator, which work together to circulate the refrigerant and facilitate the transfer of heat.