Search NASA⌕ Search

Engineering topics

Wineland, D. J.

Publications and source records attributed to Wineland, D. J..

Laser-free trapped-ion entangling gates with simultaneous insensitivity to qubit and motional decoherence

The dominant error sources for state-of-the-art laser-free trapped-ion entangling gates are decoherence of the qubit state and the ion motion. The effect of these decoherence mechanisms can be suppressed with additional control fields or with techniques that have the disadvantage of reducing gate speed. In this study, we propose using a near-motional-frequency magnetic field gradient to implement a laser-free gate that is simultaneously resilient to both types of decoherence, does not require additional control fields, and has a relatively small cost in gate speed.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Frequency and time standards based on stored ions

The method of ion storage provides a basis for excellent time and frequency standards. This is due to the ability to confine ions for long periods of time without the usual perturbations associated with confinement (e.g., wall shifts). In addition, Doppler effects can be greatly suppressed. The use of stored ions for microwave frequency standards and the future possibilities for an optical frequency standard based on stored ions are addressed.

Bollinger, J. J.↗

Prospects for stored ion frequency standards

Fundamental limitations of possible frequency standards based on stored ions are examined. Practical limitations are also addressed but without regard to size, power consumption, and cost. With these guidelines, one can anticipate that a stored ion frequency standard with accuracy and stability better than 10 to the -15th power is now possible.

Wineland, D. J.↗

Limitations on long-term stability and accuracy in atomic clocks

The limits to accuracy and long term stability in present atomic clocks are examined. Recent proposals for new frequency standards are discussed along with the advantages and disadvantages of frequency standards based on such ideas as laser transitions, single atoms, and atom cooling. The applicability of some of these new techniques to existing standards is examined.

Wineland, D. J.↗