What's new

China Quantum Communiations Technology: Cryptography, Radar, Satellite, Teleportation, Network

Key Lab of Quantum Information of CAS (Chinese Academy of Science) recently makes a new breakthrough in quantum technology. A quantum transducer for OAM (Orbital Angular Momentum) qubits, OAM-polarization hybrid-entangled states, and OAM-entangled states, is reported for the first time. Nonclassical properties and entanglements are demonstrated following the conversion process by performing quantum tomography, interference, and Bell inequality measurements. The results demonstrate the capability to create an entanglement link between different quantum systems operating in a photon’s OAM degrees of freedom, which will be of great importance in building a high-capacity OAM quantum network.

The key research results are published in the [Light: Sci. & Appl. 5, e16019 (2016)], and [Phys. Rev. Lett. 117, 103601(2016)]

Background:
Entanglement is a vital resource for realizing many tasks such as teleportation, secure key distribution, metrology, and quantum computations. To effectively build entanglement between different quantum systems and share information between them, a frequency transducer to convert between quantum states of different wavelengths while retaining its quantum features is indispensable. Information encoded in the photon’s orbital angular momentum (OAM) degrees of freedom is preferred in harnessing the information-carrying capacity of a single photon because of its unlimited dimensions.

中国实现轨道角动量光子的量子频率转换

发布时间:2016-09-01 【字号: 小 中 大 】
  中国科学院院士、中国科学技术大学教授郭光灿领导的中科院量子信息重点实验室在轨道角动量(OAM)光子的量子频率转换研究领域取得系列进展:该实验室教授史保森领导的小组在国际上首次实现了OAM单光子、OAM纠缠光子以及OAM与偏振组成的混合纠缠光子的频率上转换,证明了在频率变换过程中单光子的量子相干性和光子对的纠缠特性保持不变。主要研究成果分别发表在《光:科学与应用》和8月29日的《物理评论快报》上。论文的第一作者为博士后周志远。
 
"The Quantum Eye" - Single-pixel 3D camera

6351321829924538693D%E7%9B%B8%E6%9C%BA2.jpg


63513242076869550120130827231402.jpg


6351321847987810413D%E7%9B%B8%E6%9C%BA.jpg


This was in 2013. Don't know what headway the "Post-80s Team" from the Shanghai Institute of Optics and Fine Mechanics has made since.

@Bussard Ramjet :lol::D
 
LOL

Please allow to answer your question.

As I told you, creator of the quantum technology is the provider of the quantum encryption machine. The quantum encryption machine features method on how to encode and decode a message through the used of encrypting in a photon.

In order to explain how a third party can't read that message, I can on and on and I"m afraid you won't be able to understanding if you don't understand quantum mechanics. So I keep it simple.

In this quantum machine, we will used LED to create photon because of LED inherently unpolarized nature. This means an unpolarized photon can exhibited all state of its spin ( like left, right, up, and down displaying all of its spin property all at once). This is what we called the wave function of how light behaves in quantum physics. And the advantage of an unpolarized photon is it makes a photon spin state unpredictable. So in order to regulate the 4 spins to a single spin property, you will need to send an unpolarized photon through a polarized filter before send off to the receiver which then used to decode the spin in the photon using the same filter the sender used, otherwise the property of the original spin in that photon message will be throw off. And spin will be represented by the traditional method of how communication technology communicate with each other, through binary of 1 and 0. This means 1 can be corresponded to left/right spin, and 0 can be up/down spin, unlike in traditional encryption, the message is displaying just binary. In quantum, you take a step further and display its spin but these spins are represented by binary, which only the sender knows because he/she is the guy that set the spin correspondence. So a third party can try to eardrop by placing a filter to intercept the message, but the beauty is like I said before, the nature of quantum entanglement caused photon spins to change once it is being observed. Thus the whole encryption will break off.

Because we are one of the few country that know how to create this quantum machine and be able to put it in space and able to deliver sensitive message over vast distance as opposed to the earlier limitation of quantum cryptography. And the fact the breakthrough in quantum communication will lead to quantum computer with the power of all known current supercomputer put together that don't even compare. So if you want to be safe from hacking proof from Uncle Sam, you might want to use our technology. This will have enormous impact in many industry that wants to keep data safe. In fact, we invest in quantum technology because we are the biggest victim of hacking groups across the world. LOL

Like I said and I predict in the future, only two countries are capable of hacking everyone system and that is us and USA because of our research in quantum computer far advance than everyone else in the world. So you can use our technology or not, it is up to you but do know if you don't, then be ready that we can hack into all of systems.
ah thanks for the long post. not too bad.

quantum encryption may be uncrackable now by the current technology, but who can predict the future? can you?
besides quantum encryption strongest advantage is its biggest disadvantage: vulnerability for denial of service attack. how do you want to address this issue?

so China uses LED for emitting light aka creating photon because of its inherently unpolarized nature. how about laser light? single mode and multi-mode laser? is laser light always polarized? besides, both LED and laser are electromagnetic waves by nature, and as such they can be both.

I believe quantum has 6 states: 0, 1, early, late, overlap and nil. maybe it is china quantum tech when you say 4 states with 1 and 0, with 1 can be left/right spin and 0 can be up/down spin.

but I am not an expert in quantum physics. other can explain better.


re-edit: 6 states
 
Last edited:
So, when are we getting that ? 8-) I mean we r already using Beidou navigation system. Next year we will launch our satellite too. I mean we are closely cooperating with China in this regard...


Can't find any news yet but is very natural for allies to use common platforms, let's wait and see.
 
ah thanks for the long post. not too bad.

quantum encryption may be uncrackable now by the current technology, but who can predict the future? can you?
besides quantum encryption strongest advantage is its biggest disadvantage: vulnerability for denial of service attack. how do you want to address this issue?

so China uses LED for emitting light aka creating photon because of its inherently unpolarized nature. how about laser light? single mode and multi-mode laser? is laser light always polarized? besides, both LED and laser are electromagnetic waves by nature, and as such they can be both.

I believe quantum has 6 states: 0, 1, early, late, overlap and nil. maybe it is china quantum tech when you say 4 states with 1 and 0, with 1 can be left/right spin and 0 can be up/down spin.

but I am not an expert in quantum physics. other can explain better.


re-edit: 6 states
Defeating quantum encryption is breaking physics at the subatomic level. That's not possible. You can't beat randomness. DOS attack is largely non-existence if the message transmission is being ping back and forth between the ground station and satellite. It is not going through optical fiber.

The EM wave propagation of LASER, regardless of what type, has a linear electric field oscillation, which mean the direction that the spin in that photon is predicable, and thus does not exhibit the same randomness as typical light wave. This means it is not an unpolarized light that can be used for quantum computer. Though laser light is better used to trigger fusion in the energy fusion realm since it focuses on a localized target.

All lights contains both the electric and magnetic field in the EM wave but each will transverse in opposite direction. Though we concern with only the electric field here because that how you determine whether one is polarized or not polarized. In this case, the electric field which is the spin of the photon has only 4 states in the space plane, either up, down, left, right or vertical up, vertical down, horizontal left, horizontal right. Whatever the case may be, the sender can used binary of 1 and 0, like I said, to represent of each of those photon's electric spin state. But since the quantum cryptographer wants randomness or the unpredictability of the photon state to make guessing impossible before it sends to an optical filter, they want the unpolarized light.
 
Yes. I agree.

Sorry, I wrote satellite will b launched next year but it is actually will be in 2018. Here is the link.......

https://propakistani.pk/2016/08/30/pakistan-china-jointly-launch-satellite-2018/


Look forward to that! Space is a critical frontier, if not ultimate, for civil apps as well as for top-level national security. China and Pakistan are in their own camp, developing own standards from satellite positioning to manned space explorations, let there be more joint programs!
 
Defeating quantum encryption is breaking physics at the subatomic level. That's not possible. You can't beat randomness. DOS attack is largely non-existence if the message transmission is being ping back and forth between the ground station and satellite. It is not going through optical fiber.

The EM wave propagation of LASER, regardless of what type, has a linear electric field oscillation, which mean the direction that the spin in that photon is predicable, and thus does not exhibit the same randomness as typical light wave. This means it is not an unpolarized light that can be used for quantum computer. Though laser light is better used to trigger fusion in the energy fusion realm since it focuses on a localized target.

All lights contains both the electric and magnetic field in the EM wave but each will transverse in opposite direction. Though we concern with only the electric field here because that how you determine whether one is polarized or not polarized. In this case, the electric field which is the spin of the photon has only 4 states in the space plane, either up, down, left, right or vertical up, vertical down, horizontal left, horizontal right. Whatever the case may be, the sender can used binary of 1 and 0, like I said, to represent of each of those photon's electric spin state. But since the quantum cryptographer wants randomness or the unpredictability of the photon state to make guessing impossible before it sends to an optical filter, they want the unpolarized light.
I believe hardly anyone understands :laugh:

let me make it shorter: quantum communication is all about photon polarizations. the secret key between sender and receiver is shared by matching photon both basis and polarizations.

added: photon basis
 
Last edited:
I believe hardly anyone understands :laugh:

Then what are you complaining about on your post #39 and previous replies? As if you are that intelligent from the very beginning, now he explains more in details you have no clue what he is talking about. Get a life man.
 
Wow I can't believe so many Vietnamese members are upset by this technology. :lol:

@Viet why are you so upset? Do you think this is some sort of weapon? It's communications technology.
They are not upset. they jealous .

Then what are you complaining about on your post #39 and previous replies? As if you are that intelligent from the very beginning, now he explains more in details you have no clue what he is talking about. Get a life man.
technology and vietnamese is oxymoron man. But i smell the fear in vietnamese people. China is so way ahead of SEA that ranting and fearing the dragon is all they can do
:lol:
 
They are not upset. they jealous .


technology and vietnamese is oxymoron man. But i smell the fear in vietnamese people. China is so way ahead of SEA that ranting and fearing the dragon is all they can do
:lol:

yes, if you show a newspater report, vietnamese will say it is too simple, if you give out the formal paper, they will say too deep. what they really want is not the discussion of scientific problems but trolling, that only disclose their dark psychology.
 
That does not explain anything how it works in principle:

photon teleportation, quantum key exchange and quantum communications between Beijing and Vienna via a satellite.

Nothing is revealed what technology is used.

Read the Nature paper when it comes out. It's not like Pan Jianwei (the project lead) has a shortage of those - he started this project 10 years ago and has demonstrated it repeatably at smaller scales, as well as won the Fresnel Prize in Quantum Optics in 2005 from the European Physical Society.
 
yes, if you show a newspater report, vietnamese will say it is too simple, if you give out the formal paper, they will say too deep. what they really want is not the discussion of scientific problems but trolling, that only disclose their dark psychology.
I never say be an expert in quantum communications. So before you start trolling me, I challenge you to find what I say on encryption technology and quantum physics is wrong!
 
Read the Nature paper when it comes out. It's not like Pan Jianwei (the project lead) has a shortage of those - he started this project 10 years ago and has demonstrated it repeatably at smaller scales, as well as won the Fresnel Prize in Quantum Optics in 2005 from the European Physical Society.
Bro, that's good. Can you predict how many Prof. Pan like will appear in the 10 years.
 
http://en.people.cn/n3/2016/0908/c98649-9112553.html

China successfully develops quantum radar system
(People's Daily Online) 14:41, September 08, 2016

China launches the world's first quantum satellite on top of a Long March-2D rocket fromthe Jiuquan Satellite Launch Center in Jiuquan, northwest China's Gansu Province, Aug. 16, 2016. This world's first quantum communication satellite is given the moniker "Micius,"after a fifth century B.C. Chinese scientist. (Xinhua/Jin Liwang)

The 14th Institute of China Electronics Technology Group Corporation (CETC) hassuccessfully developed China’s first quantum radar system last month, Xinhua NewsAgency reported. The system, which is based on the technology of single photon detection,counts as yet another major milestone for China in quantum research.

The quantum radar system was developed by the Intelligent Perception TechnologyLaboratory of the 14th Institute of CETC. Researchers completed experiments onquantum detection and target scattering characterization. In the target detectionexperiment, conducted in a real atmospheric environment, the detection ability of thesystem was proven to be over 100 kilometers.

According to a Sept. 8 report by Mingbao Daily, the theoretical basis of the quantum radaris that an object will change its quantum properties after receiving photonic signals. Thequantum radar can easily detect stealth aircraft and is highly resistant to becomingjammed. Military experts have stated that once a stealth aircraft is located by the radar, itstands little chance to escape the strikes of air defense missiles.
 
Back
Top Bottom