Quantum channel

hide

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.


News tagged with quantum communication

results timeline


Researchers Set New Distance Record for Quantum Key Distribution

Researchers Set New Distance Record for Quantum Key Distribution

Physics / Quantum Physics

created Jul 21, 2009 | popularity 4.9 / 5 (14) | comments 4

(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 ...


Quantum communication through synergy

Physics / General Physics

created Jan 19, 2009 | popularity 4.4 / 5 (11) | comments 0

(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 ...


Long-Lasting Quantum Memory Leads to Long-Distance Quantum Communication

Long-Lasting Quantum Memory Leads to Long-Distance Quantum Communication

Physics / General Physics

created Oct 07, 2008 | popularity 4.3 / 5 (54) | comments 6

(PhysOrg.com) -- Physicists have taken a step closer to realizing long-distance quantum communication, in which a quantum state is transferred from one location to another by becoming entangled with a traveling ...


In quantum channels, zero plus zero can equal non-zero

In quantum channels, zero plus zero can equal non-zero

Physics / General Physics

created Oct 06, 2008 | popularity 4.6 / 5 (62) | comments 12

(PhysOrg.com) -- Physicists have discovered a strange characteristic of quantum communication channels. If two quantum channels each have a transmission capacity of zero, they may still have a nonzero capacity ...


Straightening messy correlations with a quantum comb

Straightening messy correlations with a quantum comb

Physics / Quantum Physics

created Nov 23, 2009 | popularity 4.8 / 5 (10) | comments 0

Quantum computing promises ultra-fast communication, computation and more powerful ways to encrypt sensitive information. But trying to use quantum states as carriers of information is an extremely delicate ...


Scientists develop novel ion trap for sensing force and light

Scientists develop novel ion trap for sensing force and light

Physics / General Physics

created Jul 01, 2009 | popularity 5 / 5 (3) | comments 0

Miniature devices for trapping ions (electrically charged atoms) are common components in atomic clocks and quantum computing research. Now, a novel ion trap geometry demonstrated at the National Institute ...


Quantum calibration paves way for super-secure communication

Quantum calibration paves way for super-secure communication

Physics / General Physics

created Nov 17, 2008 | popularity 4.3 / 5 (11) | comments 2

(PhysOrg.com) -- A new approach to calibrating quantum mechanical measurement has been developed with particular applications in optics and super-secure quantum communication.


How Bob Detects Possible Errors in the Coding of Alice's Message

Viterbi Algorithm goes quantum

Physics / General Physics

created Jul 31, 2008 | popularity 4.8 / 5 (11) | comments 0

The Viterbi Algorithm, the elegant 41-year-old logical tool for rapidly eliminating dead end possibilities in data transmission, has a new application to go alongside its ubiquitous daily use in cell phone ...


Scientists to study diamond-based quantum information processing, communication

Physics / Quantum Physics

created Apr 15, 2009 | popularity 3.3 / 5 (3) | comments 0

(Santa Barbara, Calif.) -- In the quest for quantum information processing, diamonds may be a physicist's best friend.