Researchers from the National Institute of Standards and Technology (NIST) have demonstrated the accurate control of rapid acceleration and instantaneous stops of their beryllium ions in an ion trap.
A close resemblance is a marble placed at the bottom of a bowl, wherein the marble oscillates too and forth during the sudden acceleration of the bowl and comes to rest along with the bowl when it is stopped suddenly.
The researchers believe that their speedy ions hold potential in future quantum computers because electron energy levels of their atomic marble are not affected, which is essential for a quantum computer, wherein data stored at these energy levels may have to be moved around without sacrificing the information content. With ion quantum bits or qubits, this can be achieved through the physical movement of the ions. Previously, the duration of moving ions was much longer than that of logic operations on the ions. Now, the duration is almost equal, which in turn decreases processing overhead, thus enabling the ions to move and to be ready for reuse much quicker than before.
In the experiment, trapped ions were cooled down to their lowest quantum energy state of motion. Then, one and two ions were transported across hundreds of micrometers within a multi-zone trap. Fast acceleration excites the undesirable oscillatory motion of the ions; however, the NIST scientists controlled the deceleration efficiently to return the ions to their initial quantum state when they stopped. A research team from Mainz, Germany has reported similar results.
Using fast field programmable gate array technology, NIST scientist, Ryan Bowler programmed the voltage levels and timescales applied to different electrodes in the ion trap. The even voltage supply enables the ions to move very quickly without getting too agitated. With advancements in precision control, scientists believe that faster transportation and quicker return to original quantum state of the ions when they stop are possible. Scientists must also focus on several other practical issues such as undesirable heating of the ion movement from noisy electric fields in the environment.