A process including: magnetically energizing susceptible magnetic particles; and accumulating the resulting terahertz lasing mode output of the particles. The mirrors are configured to form an optical pathway for closed reflection and transmission of the optical pulse within the enhancement cavity. A piston comprising non-metallic, heat resistant material is disposed in the pumping chamber. The transmission power level for a communication from the base station is based, in part, on weighting the path loss estimate in response to the quality of the estimate.