News tagged with quantum communication
Trade-off coding for quantum communication provides more benefits than previously thought
(Phys.org) -- In optical communication systems, the overall performance depends on the strategy used to transmit photons from one location to another. In previous attempts to optimize this performance, scientists ...
Apr 16, 2012 |
4.4 / 5 (9) |
0
|
Proposed experiment offers new way to generate macroscopic entanglement
(PhysOrg.com) -- In the development of quantum information processing, one of the key requirements is achieving quantum entanglement. But recently, physicists have been investigating other forms of quantum correlations besides ...
Jan 05, 2012 |
4.9 / 5 (20) |
2
|
New way to store light could prove useful for optical communication
(PhysOrg.com) -- Due to its high data carrying capacity and low loss, light can serve as an ideal information carrier. However, due to the high speed at which it travels, light is difficult to store. Because ...
Oct 03, 2011 |
4 / 5 (10) |
3
|
Reducing noise in quantum operation at room temperature
(PhysOrg.com) -- "A quantum memory is a crucial component of future quantum information processing technologies. Among these technologies, a quantum communications system based on light will enable vastly improved performance ...
Aug 23, 2011 |
5 / 5 (4) |
3
|
Physicists offer countermeasure to new quantum eavesdropping attack
(PhysOrg.com) -- As early communications systems using quantum cryptography become commercially available, physicists have been investigating new types of security attacks in an effort to defend against them. ...
Jul 25, 2011 |
3.9 / 5 (9) |
0
|
Vertical cavity quantum switch could lead us away from electronics-based computing
(PhysOrg.com) -- Right now, many researchers around the world are working on ways to move away from electronics-dominated computing systems. There are a number of ideas about how this can be accomplished. "We are trying to ...
Jun 30, 2011 |
4.4 / 5 (27) |
5
|
Physicists describe how to make time-reversed light pulses
(PhysOrg.com) -- By taking advantage of the properties of periodic systems, physicists have described how to efficiently time-reverse ultrashort electromagnetic pulses. Since a time-reversed pulse evolves ...
May 31, 2011 |
4.4 / 5 (17) |
44
|
Entanglement can help in classical communication
(PhysOrg.com) -- When most of us think of entanglement, our minds jump immediately to quantum communication. "Entanglement has become very well known and useful in quantum communication," Robert Prevedel tells PhysOrg.com. Preved ...
Mar 30, 2011 |
4.3 / 5 (17) |
14
|
Single photon solid-state memory for telecommunications
(PhysOrg.com) -- One of the issues associated with quantum information schemes revolves around the ability to develop quantum memories that allow for the retrieval of information on demand. Overcoming this ...
Mar 08, 2010 |
4.6 / 5 (20) |
5
|
Long-distance quantum communication gets closer as physicists increase light storage efficiency by an order of magnitude
(PhysOrg.com) -- In a new demonstration of reversible light storage, physicists have achieved storage efficiencies of more than a magnitude greater than those offered by previous techniques. The new method could be useful ...
Mar 01, 2010 |
4.2 / 5 (25) |
10
|
Researchers Set New Distance Record for Quantum Key Distribution
(PhysOrg.com) -- Quantum key distribution (QKD) could be the next commercial success of quantum physics, and a recent study has taken the field a step closer to this reality. Researchers from the University ...
Jul 21, 2009 |
4.9 / 5 (14) |
4
Post-Quantum Correlations: Exploring the Limits of Quantum Nonlocality
(PhysOrg.com) -- When it comes to nonlocal correlations, some correlations are more nonlocal than others. As the subject of study for several decades, nonlocal correlations (for example, quantum entanglement) ...
May 07, 2009 |
4 / 5 (22) |
20
Entangled Light in Bose-Einstein Condensates
(PhysOrg.com) -- When physicists entangle light, they usually use nonlinear crystals as the source. However, it’s difficult to control the entanglement generation process in a bulk crystal, and so scientists ...
Apr 08, 2009 |
4.4 / 5 (16) |
13
Quantum communication through synergy
(PhysOrg.com) -- When most people think of quantum communication, they think in terms of private communication channels - the ability to send messages without a third-party deciphering them. Indeed, quantum cryptography represents ...
Jan 19, 2009 |
4.4 / 5 (12) |
0
Nanotube-based terahertz polarizer nears perfection
(PhysOrg.com) -- Researchers at Rice University are using carbon nanotubes as the critical component of a robust terahertz polarizer that could accelerate the development of new security and communication ...
Jan 30, 2012 |
4.5 / 5 (11) |
1
|
Quantum channel
In quantum information theory, a quantum channel is a communication channel which can transmit quantum information, as well as classical information. An example of quantum information is the state of a qubit. An example of classical information is a text document transmitted over the internet.
More formally, quantum channels are completely positive, trace preserving maps between spaces of operators, as defined more precisely below.
For more information about Quantum channel, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
