How do scientists store nothing? It may sound like the beginning of a bad joke, but the answer is causing a stir in the realm of quantum physics after two research teams, including one from the University of Calgary, have independently proven it’s possible to store a special kind of vacuum in a puff of gas and then retrieve it a split second later.
In our everyday life, light is completely gone when we turn it off. In the world of quantum physics, which governs microscopic particles, even the light that is turned off exhibits some noise. This noise brings about uncertainty that can cause trouble when trying to make extremely precise measurements.
Using crystals to manipulate laser light, researchers create a peculiar type of nothingness known as a “squeezed vacuum,” which under certain conditions, exhibits less noise than no light at all. A squeezed vacuum is employed in gravitation wave detection; it is also important in the booming field of quantum information technology, where it is used to carry information and to generate an even more mysterious quantum object, entangled light.
Building on the 2001 breakthrough of Harvard-Smithsonian scientists who slowed light down to a stop, teams of physicists from the U of C and the Tokyo Institute of Technology have independently demonstrated that a squeezed vacuum can be stored for some time in a collection of rubidium atoms and retrieved when needed. In work to be published in the March 7 advanced online edition of the leading physics journal Physical Review Letters, the physicists measured the noise of the retrieved light and found it to remain “squeezed” compared to no light at all.
“Memory for light has been a big challenge in physics for many years and I am very pleased we have been able to bring it one step further,” said Alexander Lvovsky, professor in the Department of Physics and Astronomy, Canada Research Chair and leader of the U of C’s Quantum Information Technology research group. “It is important not only for quantum computers, but may also provide new ways to make unbreakable codes for transmitting sensitive information”.
"I'm very impressed," physicist Alexander Kuzmich of the Georgia Institute of Technology in Atlanta told the American Association for the Advancement of Science’s ScienceNOW news service of the squeezed vacuum discovery. Kuzmich, who was able to store and retrieve a single photon in 2006, said the development could help create new types of quantum networks for ultra-secure information transmission and help spell out the boundary of the quantum realm. "It's a real technical achievement," he said.
Lvovsky’s team is continuing work on light storage and is now investigating the possibility of storing more complex forms of quantum light, such as entangled light, which has a wide range of applications for quantum computing and information exchange.
Grady Semmens | EurekAlert!
A quantum walk of photons
24.05.2017 | Julius-Maximilians-Universität Würzburg
Scientists propose synestia, a new type of planetary object
23.05.2017 | University of California - Davis
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
23.05.2017 | Event News
22.05.2017 | Event News
17.05.2017 | Event News
24.05.2017 | Life Sciences
24.05.2017 | Life Sciences
24.05.2017 | Physics and Astronomy