A research team from the National Institute of Standards and Technology (NIST) has developed a tunable superconducting circuit on a chip. It has been designed to place one microwave photon in two colors, or frequencies, concurrently.
The developed prototype is a microwave "superposition” chip-scale microwave version of an optics test, in which a beam-splitter propels a photon in any one of the two possible tracks across a table of lenses, lasers and mirrors. The new circuit developed by NIST researchers can be used to generate and manipulate various quantum states.
A report titled ,”Quantum superposition of a single microwave photon in two different ’colour’ states,” and published in the July issue of Nature Physics explains that the prototype microwave-based bit for optical linear quantum computing was created by the NIST researchers to accumulate information and store it in the frequency of the photon. The circuit is built of a distinct source for generating photons, a cavity that vibrates/resonates naturally at specific frequencies and a SQUID (superconducting quantum interference device), which is a coupling device.
The researchers influenced a photon to oscillate between various superpositions after tuning the properties of the SQUID to pair 2 reverberating frequencies of the cavity. This resulted in the photon switching back and forth from 50/50 equal proportions of both the frequencies to an unequal 75/25 split, thus trapping the photons in the cavity.
A physicist at NIST and a co-author of the paper, José Aumentado stated that the novel method of manipulating the box-trapped microwave quantum states can be applied to generate quantum states within superconductor resonators and other chip-scale devices.
Source: http://www.nist.gov/