Abstract

Position measurements of neutral atoms with optical techniques and with a resolution better than the wavelength of light are of considerable interest both theoretically and practically. The prototype of an all-optical measuring device is the Heisenberg microscope. In this case, the precision of the measurement can be no better than the wavelength. However, for particles with internal degrees of freedom new position-measurement schemes are proposed. For example, an atom can be localized by measuring the phase shift of an optical field in a standing-wave cavity crossed by the atom.² A similar scheme to determine atomic momentum by using a traveling wave in a ring cavity has also been suggested.² In addition, a variation of the Heisenberg microscope has been demonstrated experimentally.³

© 1994 Optical Society of America