Along those lines, you might want to read - "PROGRESS ON DUAL LASER EXPERIMENTS" http://www.lenr-canr.org/acrobat/Hagelsteinprogresson.pdf
EXCERPT: We have continued our experiments using duel laser stimulation of electrochemically loaded PdDx. In earlier work, we used two properly oriented and polarized tunable diode lasers which provided stimulation at optical frequencies; interestingly, we found that the excess heat issensitive to the beat difference frequency. Low-level thermal signals are observed to be triggered at apparent resonances when the difference frequency is 8.3, 15.3 and 20.4 THz Perhaps, also related is the ultrasonic "Superwave" LENR stimulation used by Energetics Technologies - http://lenr-canr.org/acrobat/DardikIultrasonic.pdf My impression is that their source has a wideband discrete spectrum of phase-locked frequencies - so that the same stimulus signal is repeatedly swept.
