A new method for searching for free fractional charge particles in bulk matter

We present a new experimental method for searching for free fractional char ge in bulk matter; this new method derives from the traditional Millikan li quid drop method but allows the use of much larger drops, 20-100 mu m in di ameter, compared to the traditional method that uses drops less than 15 mu m in diameter. These larger drops provide the substantial advantage that it is then much easier to consistently generate drops containing liquid suspe nsions of powdered meteorites and other special minerals. These materials a re of great importance in bulk searches for fractional charge particles tha t may have been produced in the early universe. (C) 2000 American Institute of Physics. [S0034-6748(00)05709-9].