A team of researchers from Austria is pushing the envelope of quantum computing through high-precision control of the quantum entanglement phenomenon. Experimental physicist Rainer Blatt, at the University of Innsbruck (UoI) in Austria, is one of quantum computing’s pioneers and one of the most active researchers in this field (quantum computing).
One of the keys to opening the door to quantum computing is to make controllable qubits to allow quantum properties to be exploited for information encoding and processing. Already, in 2011, a team led by Rainer Blatt managed to create a quantum register containing 14 controllable ultracold ions (qubits), a record at the time.
Then, as we reported last month, the Blatt team went even further and broke their own record by creating a multi-particle entanglement system made of 20 addressable and individually controllable qubits. Now, Prof. Blatt and his team at the Institute for Quantum Optics and Quantum Information have made another achievement that brings quantum entanglement even closer to practical applications.
Toward Ultra-Precise Quantum Instruments
After acquiring the ability to generate and manipulate an entangled system and individually address particles within it, Blatt’s team has now gone a step further. This time, they found a way to control the light emission rate of a single photon in an entangled separated pair. The team worked on barium atoms and investigated two scenarios where the particles are either entangled or not entangled and compared the photon interference generated between the two cases.
Gabriel Araneda, a member of the research team, explained that: “The measurements showed that these are qualitatively different.
In fact, the measured difference of the interference fringes directly corresponds to the amount of entanglement in the atoms. In this way we can characterize the entanglement fully optically.”
The ability to observe and control light emissions of entangled emitters (quantum interference) would pave the way to the development of specific quantum instruments with “previously unknown precision”.
“We take advantage of this sensitivity and use the observed interference signal to measure magnetic field gradients. This technique may lead to the development of ultra-sensitive optical gradiometers. As the measured effect does not rely on the proximity of the atoms, these measurements could allow to precisely comparing field strengths at separated locations, such as that of the Earth’s magnetic or gravitational fields,” said researchers.
Professor Rainer Blatt and his team have been very successful in unlocking some secrets of quantum entanglement, and this makes us excited as to what their next research efforts could be.