Selective melanin-based photothermolysis with a free running pulsed ruby laser seems to be a promising, noninvasive technique for long-term hair removal. More than one treatment is necessary since only anagen hair will be affected.

We report the observation of terahertz oscillations in transient transmission measurements following femtosecond UV photolysis of I−3 in ethanol solutions. Transmission signals at 620 nm and at 880 nm, which are above and below the λmax of the known absorption of I−2 oscillate at precisely opposite phase. This and other results presented indicate that though the oscillations we are observing coherent vibration of the I−2 photofragment.

The 2 msec pulsed Alexandrite laser technology is effective for the removal of unwanted hairs, ranging from fair to dark, except when hairs are absent in the shaft depending on the stage of their growth cycle. This results in the necessity of a few treatments or touchups. Adverse effects are minimal and transient.

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