Not 1, not 2, not 3, but 4 clones!
Xi-Jun Ren and Yang Xiang from Henan Universities in China, in collaboration with Heng Fan at the Institute of Physics of the Chinese Academy of Sciences, have produced a theory for a quantum cloning machine able to produce several copies of the state of a particle at atomic or sub-atomic scale, or quantum state, in an article about to be published in EPJ D ¹. This could have implications for quantum information processing methods used, for example, in message encryption systems.
Quantum cloning is difficult because quantum mechanics laws only allow for an approximate copy—not an exact copy—of an original quantum state to be made, as measuring such a state prior to its cloning would alter it. In this study, researchers have demonstrated that it is theoretically possible to create four approximate copies of an initial quantum state, in a process called asymmetric cloning.
The authors have extended previous work that was limited to quantum cloning providing only two or three copies of the original state. One key challenge was that the quality of the approximate copy decreases as the number of copies increases. The authors were able to optimise the quality of the cloned copies, thus yielding four good approximations of the initial quantum state.
They have also demonstrated that their quantum cloning machine has the advantage of being universal and therefore is able to work with any quantum state, ranging from a photon to an atom.
Assymetric quantum cloning has applications in analysing the security of messages encryption systems, based on shared secret quantum keys. Two people will know whether their communication is secure by analysing the quality of each copy of their secret key. Any third party trying to gain knowledge of that key would be detected as measuring it would disturb the state of that key.
More information: Ren XJ, Xiang Y and Fan H (2011). Optimal asymmetric 1 –> 4 quantum cloning in arbitrary dimension. European Physical Journal D. DOI 10.1140/epjd/e2011-20370-2
Provided by Springer
-
From lemons to lemonade: Reaction uses carbon dioxide to make carbon-based semiconductor,
32 comments
-
Thioridazine kills cancer stem cells in human while avoiding toxic side-effects of conventional cancer treatments,
3 comments
-
SpaceX private rocket blasts off for space station (Update),
42 comments
-
Climate scientists say they have solved riddle of rising sea,
31 comments
-
SpaceX capsule has 'new car' smell, astronauts say (Update),
4 comments
-
Why does light move?
56 minutes ago
-
How to calculate the repulsion force between a permanent and an electromagnet?
2 hours ago
-
Why does light allow us to see things?
2 hours ago
-
Room temperature superconductivity
2 hours ago
-
Water flow question
5 hours ago
-
16 year old solves 300 year old problem set by Isaac Newton
6 hours ago
- More from Physics Forums - General Physics
More news stories
Is a classical electrodynamics law incompatible with special relativity?
(Phys.org) -- The laws of classical electromagnetism that were developed in the 19th century are the same laws that scientists use today. They include Maxwell’s four equations along with the Lorentz la ...
May 24, 2012 |
4.7 / 5 (17) |
43
|
Landmark calculation clears the way to answering how matter is formed
(Phys.org) -- An international collaboration of scientists, including Thomas Blum, associate professor of physics, is reporting in landmark detail the decay process of a subatomic particle called a kaon – ...
May 25, 2012 |
4.3 / 5 (22) |
51
|
Lying in wait for WIMPs: Researchers seek to dramatically increase sensitivity of Large Underground Xenon detector
Although it's invisible, dark matter accounts for at least 80 percent of the matter in the universe. No one knows what it is, but most scientists would bet on weakly interacting massive particles, or WIMPs.
May 23, 2012 |
4 / 5 (7) |
16
|
Hawaii lab turns laser-powered bubbles into microrobots
(Phys.org) -- A team of scientists from the University of Hawaii are working on microrobots created from bubbles of air in a saline solution. The bubbles take on their title of “robots” as a laser ...
May 23, 2012 |
5 / 5 (4) |
2
|
Sound increases the efficiency of boiling
Scientists at the Georgia Institute of Technology achieved a 17-percent increase in boiling efficiency by using an acoustic field to enhance heat transfer. The acoustic field does this by efficiently removing vapor bubbles ...
May 24, 2012 |
5 / 5 (2) |
2
Land and sea species differ in climate change response: study
(Phys.org) -- Marine and terrestrial species will likely differ in their responses to climate warming, new research by Simon Fraser University and Australia’s University of Tasmania has found.
'Unzipped' carbon nanotubes could help energize fuel cells, batteries
Multi-walled carbon nanotubes riddled with defects and impurities on the outside could replace some of the expensive platinum catalysts used in fuel cells and metal-air batteries, according to scientists at ...
T cells 'hunt' parasites like animal predators seek prey, study shows
By pairing an intimate knowledge of immune-system function with a deep understanding of statistical physics, a cross-disciplinary team at the University of Pennsylvania has arrived at a surprising finding: T cells use a movement ...
Computer model used to pinpoint prime materials for efficient carbon capture
When power plants begin capturing their carbon emissions to reduce greenhouse gases – and to most in the electric power industry, it's a question of when, not if – it will be an expensive undertaking.
Change in developmental timing was crucial in the evolutionary shift from dinosaurs to birds: study
At first glance, it's hard to see how a common house sparrow and a Tyrannosaurus Rex might have anything in common. After all, one is a bird that weighs less than an ounce, and the other is a dinosaur that ...
Nvidia trumpets Tegra 3 phone design wins for 2012
(Phys.org) -- Nvidia’s competitive war paint has a name, Tegra 3. On the heels of Nvidia announcements about lowering costs of its Tegra 3 processors and Nvidia-enabled tablets running Android Ice Cream ...
Nov 04, 2011
Rank: 1 / 5 (1)
Nov 04, 2011
Rank: 4.7 / 5 (6)
Please look up entanglement. It does not allow for the transmission of information (superluminal or otherwise).
Transmitting information requires a priori knowledge of a state (i.e. you have to encode information onto your medium in order to transmit anything).
Entanglement does not allow for that as such encoding would be a measurement/alteration of the state of one entity of the entangled pair. Such a an alteration does NOT get tranmitted to the other entity.