Pathway Selective Pulses

Determining the availability of evolution pathways in quantum systems, which is important to a variety of spectroscopies, is often accomplished with a pathway selection scheme (PSS). In the absence of pulsed field gradients, the availability of an evolution pathway is only determined after combining the results from <i>multiple</i> experiments in a PSS. In this work, we provide a general method for determining the availability of evolution pathways within a <i>single</i> experiment by converting a PSS into a pathway selective pulse (PSP) sequence that excites the quantum system only if the selected pathways are available. Liquid-state NMR demonstrations of a PSP that nutates a spin only in the presence of heteronuclear coupling is presented