It was beyond any understanding and a shocking surprise when Roland Sauerbrey (1996) measured ultrahigh acceleration of macroscopic objects having densities in the range of the solid state. These accelerations were over 10,000 times higher than ever measured before in a laboratory. His convincing measurement at laser interaction with a target was easily seen by the Doppler blue shift of spectral lines in the reflected light. Sauerbrey’s mention of this most extraordinary observation was hidden in the abstract of a long paper. Why was no exceptional attention given to this fact? One problem was that extremely high-quality lasers were needed, as discovered and clarified by Jie Zhang (1998); see the third paragraph of Chapter 8.
The acceleration was on the order of a billion billion times higher than Earth’s gravitational acceleration g. It was well known from studies of laser interaction with targets that very high accelerations of dense blocks of materials could be produced by the largest laser on Earth at the National Ignition Facility (NIF) in Livermore, California. It could heat a metal surface and ablate it from the generated plasma by an acceleration of a thousand billion times faster than g. This remarkable result was achieved with very short laser pulses of one thousandth of a millionth of a second (a nanosecond, or ns).
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