The physicists at The University of Bonn and the Technion - Israel Institute of Technology have recently devised a sophisticated experiment to find out which factors identify the speed of a quantum computer in terms of making computations.
A EurekAlert! report specified that quantum computers are incredibly sophisticated machines that depend on the principles of a quantum method for the processing of information.
It allows them to handle specific problems in the future that are totally unsolvable for conventional computers. Nonetheless, for quantum computers, fundamental limits are applicable for the amount of data processed in a given time.
Quantum Gates
The information stored in conventional computers can be believed as a "long sequence of zeros and ones, the bits," explained the physicist in their study published in Science Advances.
They added, in quantum mechanics, it is different. Specifically, the information is stored in quantum bits similar to a wave instead of a series of discrete values.
Physicists speak of wave functions when they want to represent the information controlled in qubits accurately.
Information in a traditional computer is linked together by the so-called "gates." Integrating numerous gates enables elementary computations like the two bits' addition.
The information is processed similarly in quantum computers, where quantum gates are changing the wave function based on specific rules.
Quantum gates, a similar ScienceDaily report said, resemble their traditional relatives in a separate respect. Dr. Andrea Alberti of the Institute of Applied Physics at the University of Bonn said even in the quantum world, gates are not working infinitely fast.
She added that they require a minimum amount of time to transform the wave function and the information this has.
Rolling Down Like Marbles in a Light Bow
Over seven decades back, Leonid Mandelstam and Igor Tamm, Soviet physicists, assumed this minimum time to transform the wave function.
For the first time, the University of Bonn and the Technion physicists have now examined this Mandelstam-Tamm limit to investigate a multifaceted quantum system.
To do this, they used cesium atoms that moved in a highly controlled way. In the investigation, the physicists enabled individual atoms to roll down like marbles in a light bowl and observe their motion, explained Alberti, who led the research.
Atoms can be considered as quantum mechanically "as matter waves." During the journey to the light bowl's bottom, their quantum information is changing. The study investigators now want to determine the earliest time of "deformation."
This time would then be the experimental evidence of the Mandestam-Tamm limit. However, the problem with this is that in the quantum world, each measurement of the atom's position inevitably changes the matter-wave in a foreseeable manner, as indicated in a similar Bioengineer.org report.
Therefore, it always appears like the marble has distorted, no matter how fast the measurement is made. Thus, the physicists advised a different approach to detect the deviation from the first state, explained Alberti.
The researchers, for this purpose, started by producing a replication of the matter-wave, meaning a nearly exact twin. Doctoral student Gal Ness from the Technion and the study's first author said they used fast light pulses to generate a so-called "quantum superposition" of two states of the atom.
Related information about quantum gates is shown on IBM Research's YouTube video below:
Check out more news and information on Quantum Physics in Science Times.