Defying Conventional Wisdom in Spectroscopy: Power Narrowing on IBM Quantum.

Power broadening-the broadening of the spectral line profile of a two-state quantum transition as the amplitude of the driving field increases-is a well-known and thoroughly examined phenomenon in spectroscopy. It typically occurs in continuous-wave driving when the intensity of the radiation field increases beyond the saturation intensity of the transition. In pulsed-field excitation, linear power broadening occurs for a pulse of rectangular temporal shape.