Quantum bit

Quantum bit (295)
Quantum computer (193)
Quantum computing (84)

Synopsis: Tendinte: 0_quantum computing: Quantum bit:

#Compressed bits store tons of quantum data University of Toronto Posted by Lindsay Jolivet-U. Toronto on September 29 2014scientists recently demonstrated that it s possible to compress quantum bits or qubits without losing information.

So it would require only 10 qubits to store all of the information about 1000 qubits

and only 20 qubits to store all of the information about a million. Digital compression in the world of classical information theory is fairly straightforward.

A qubit can be in a uperpositionbetween both zero and one until you measure it at

Measured one way a qubit might reveal a value of either zero or one. Measured another way it might show a value of either plus or minus.

So you don t want to collapse the quantum state of the qubit until you re ready to.

Once you ve made a single measurement any other information you might have wanted to extract from the qubit disappears.

You could just store the qubit until you know you re ready to measure its value.

or millions of qubits. ur proposal gives you a way to hold onto a smaller quantum memory

In the experiment Lee Rozema a researcher in Steinberg s lab and lead author on the paper prepared qubits in the form of photons

The experiment showed that the information contained in three qubits could be compressed into only two qubits

One caveat is that the information has to be contained in qubits that have been prepared by an identical process.

However many experiments in quantum information make use of just such identically prepared qubits making the technique potentially very useful. his work sheds light on some of the striking differences between information in the classical and quantum worlds.

information is stored in artificial structures called quantum bits and you can even see them with your bare eyes.

They did so by producing quantum bits using electrons trapped in diamonds at extremely low temperatures. These ultra-cold gemstones effectively acted as prisons trapping the electrons

First, the scientists refined a technique used to turn phosphorous atoms into qubits, the units of measurement for quantum information.

"We have demonstrated that with silicon qubit we can have needed the accuracy to build a real quantum computer.

because magnetic spin can mess with the phosphorous atoms that the qubits are made of.""In natural silicon each atom also has its own spin

which information was retained in their silicon qubits, a function known as"coherence time.""The capability of building a quantum computer from materials already widely used for building conventional computers might be this study's most significant accomplishment, however.

Basically, the device makes it possible to use double quantum dots two quantum dots joined together as quantum bits,

or qubits, which are the basic units of information in quantum computers.""I consider this to be a really important result for our long-term goal,

which is entanglement between quantum bits in semiconductor-based devices, "said collaborator Jacob Taylor, an adjunct assistant professor at the Joint Quantum Institute, University of Maryland-National Institute of Standards and Technology.

The teams created two types of quantum bits or qubits the building blocks for quantum computers that each process quantum data with an accuracy above 99%.

& Communication Technology were first in the world to demonstrate single-atom spin qubits in silicon reported in Nature in 2012 and 2013.

Now the team led by Dzurak has discovered a way to create an artificial atom qubit with a device remarkably similar to the silicon transistors used in consumer electronics known as MOSFETS.

Postdoctoral researcher Menno Veldhorst lead author on the paper reporting the artificial atom qubit says It is really amazing that we can make such an accurate qubit using pretty much the same devices as we have in our laptops and phones.

Meanwhile Morello's team has been pushing the natural phosphorus atom qubit to the extremes of performance.

Dr Juha Muhonen a postdoctoral researcher and lead author on the natural atom qubit paper notes:

The phosphorus atom contains in fact two qubits: the electron and the nucleus. With the nucleus in particular we have achieved accuracy close to 99.99%.

The high-accuracy operations for both natural and artificial atom qubits is achieved by placing each inside a thin layer of specially purified silicon containing only the silicon-28 isotope.

This isotope is perfectly nonmagnetic and unlike those in naturally occurring silicon does not disturb the quantum bit.

The next step for the researchers is to build pairs of highly accurate quantum bits. Large quantum computers are expected to consist of many thousands

or millions of qubits and may integrate both natural and artificial atoms. Morello's research team also established a world-record coherence time for a single quantum bit held in solid state.

Coherence time is a measure of how long you can preserve quantum information before it's lost Morello says.

10.1038/nnano. 2014.211 An addressable quantum dot qubit with fault-tolerant control-fidelity Nature Nanotechnology DOI:

Novel applications of'quantum dots'including lasers biological markers qubits for quantum computing and photovoltaic devices arise from the unique optoelectronic properties of the QDS

#Quantum computers take a leap forward after scientists build qubit logic gate on silicon chip A major step towards building quantum computers capable of performing formidable calculations at a fraction of the speed of current machines has been achieved.

In traditional computers available today, data is expressed in one of two states known as binary bits which are either a 1 or a 0. A quantum bit,

or qubit as it is known, can exist in both of these states at once, meaning many computations can be performed in parallel.

For example, two qubits can encode four different values while a three qubit system encodes eight different values.

This would allow new types of computers to be constructed that would far surpass the capabilities of modern super computers.

'We've demonstrated a two-qubit logic gate-the central building block of a quantum computer-and, significantly, done it in silicon.'

Their work is the first time two qubits have been able to'talk'to each other in a logic gate.

so that they can work with qubits instead of bits. Lead author Dr Menno Veldhorst, also from the University of New south wales

'We've morphed those silicon transistors into quantum bits by ensuring that each has only one electron associated with it.'

'The team has taken now out a patent on a full-scale quantum computer chip that could perform functions involving millions of qubits.

Suitable for quantum computersfor some time now, quantum dots have been considered as possible candidates for making so-called quantum bits or"qubits,

and read out individual qubits. A long-distance coupling through an appropriately designed resonator could elegantly solve this problem.

"It could also improve entanglement between quantum bits, as incoming waves of light are effectively spread out

which can be applied to sets of qubits to perform the equivalent of Boolean algebraic functions found in standard electronic logic processors also referred to as quantum gates.

qubits made from standard silicon transistors In what is likely a major breakthrough for quantum computing, researchers from the University of New south wales (UNSW) in Australia have managed for the first time to build the fundamental blocks of a quantum computer in silicon.

and the technology could scale up to include thousands, even millions of entangled quantum bits on a single chip.

and microwave radiation The technique could scale up to hold thousands, even millions of qubits on a single chip

A quantum bit, or qubit, has two awesome and confusing properties. First, it can set itself to both 0 and 1 at the same time.

And second, it can commune (or entangle) with other qubits to compound this ability. This means five entangled qubits can store

and process as much information as 32 (two to the power of five) classical bits; 10 qubits can do as much as 1, 000 classical bits;

and 300 fully entangled qubits can manipulate as many classical bits of information as there are atoms in the Universe.

You might think this would lead to much faster number-crunching over a regular computer and you'd be right, to a point.

A quantum computer can perform any operation a classical computer can, but its exponential speedups only take effect

Quantum CMOS Most of the prototype quantum computers developed so far feature a limited number of entangled qubits made from exotic and expensive materials like cesium or diamonds and which,

and which could ultimately pave the way for quantum computers with not 300 but thousands, even millions of fully entangled qubits.

Last year, UNSW scientists were able to create single"CMOS type"qubits that leveraged current transistor technology and silicon-28, a very common isotope of silicon,

Together with a single controllable qubit, this is the basic building block of a quantum computer and paves the way to quantum chips that can perform just about any operation.

and an external current and microwave field control the qubits and make them interact as needed."

"A CNOT gate is a...two-qubit gate that flips the state of the target qubit depending on the state of the control qubit,

"In our case, the target qubit flips its spin if the control qubit is pointing down.

If the control qubit is pointing up, the target qubit will remain in the same state."

"This two-qubit gate is most essential for a quantum computer and together with single qubit operations,

which we have demonstrated already with very high fidelity, provides what is called a universal gate set. This means that any gate set can be constructed out of it."

"Although their quantum computers wouldn't work at room temperature, this approach lets the researchers operate their device at approximately 1 Kelvin(-272°C,

The researchers say they have worked out a way to extend this technique to a much larger number of qubits

"Our team is looking for industrial partners to construct a chip that would contain between tens and hundreds of qubits,

so that we can demonstrate a manufacturing process that can be scaled up to the thousands or millions of qubits."

"I believe that a Si-CMOS qubit prototype containing between tens and hundreds of qubits could be made within five years,

provided we have the right level of investment and the right industry partners. Our main aim is to develop a prototype that can demonstrate that it is possible to go all the way with'Quantum CMOS

Qubits made from standard silicon transistors In what is likely a major breakthrough for quantum computing, researchers from the University of New south wales (UNSW) in Australia have managed for the first time to build the fundamental blocks of a quantum computer in silicon.

and the technology could scale up to include thousands, even millions of entangled quantum bits on a single chip.

A quantum bit, or qubit, has two awesome and confusing properties. First, it can set itself to both 0 and 1 at the same time.

And second, it can commune (or entangle) with other qubits to compound this ability. This means five entangled qubits can store

and process as much information as 32 (two to the power of five) classical bits; 10 qubits can do as much as 1, 000 classical bits;

and 300 fully entangled qubits can manipulate as many classical bits of information as there are atoms in the Universe.

You might think this would lead to much faster number-crunching over a regular computer and you'd be right, to a point.

A quantum computer can perform any operation a classical computer can, but its exponential speedups only take effect

Most of the prototype quantum computers developed so far feature a limited number of entangled qubits made from exotic and expensive materials like cesium or diamonds and which,

and which could ultimately pave the way for quantum computers with not 300 but thousands, even millions of fully entangled qubits.

Last year, UNSW scientists were able to create single"CMOS type"qubits that leveraged current transistor technology and silicon-28, a very common isotope of silicon,

Together with a single controllable qubit, this is the basic building block of a quantum computer and paves the way to quantum chips that can perform just about any operation.

and an external current and microwave field control the qubits and make them interact as needed."

"A CNOT gate is a...two-qubit gate that flips the state of the target qubit depending on the state of the control qubit,

"In our case, the target qubit flips its spin if the control qubit is pointing down.

If the control qubit is pointing up, the target qubit will remain in the same state."

"This two-qubit gate is most essential for a quantum computer and together with single qubit operations,

which we have demonstrated already with very high fidelity, provides what is called a universal gate set. This means that any gate set can be constructed out of it."

"Although their quantum computers wouldn't work at room temperature, this approach lets the researchers operate their device at approximately 1 Kelvin(-272°C,

The researchers say they have worked out a way to extend this technique to a much larger number of qubits

"Our team is looking for industrial partners to construct a chip that would contain between tens and hundreds of qubits,

so that we can demonstrate a manufacturing process that can be scaled up to the thousands or millions of qubits."

"I believe that a Si-CMOS qubit prototype containing between tens and hundreds of qubits could be made within five years,

provided we have the right level of investment and the right industry partners. Our main aim is to develop a prototype that can demonstrate that it is possible to go all the way with'Quantum CMOS

making calculations between two qubits of information possible and thereby clearing the final hurdle to making silicon quantum computers a reality.

Scientia Professor and Director of the Australian National Fabrication Facility at UNSW. ee demonstrated a two-qubit logic gate the central building block of a quantum computer and,

0 or 1. However, a quantum bit (or ubit can exist in both of these states at once, a condition known as a superposition.

A qubit operation exploits this quantum weirdness by allowing many computations to be performed in parallel (a two-qubit system performs the operation on 4 values, a three-qubit system on 8, and so on.

the ability to conduct one-and two-qubit calculations are said essential Dzurak, who jointly led the team in 2012 that demonstrated the first ever silicon qubit,

also reported in Nature. Until now, it had not been possible to make two quantum bits alkto each other and thereby create a logic gate using silicon.

But the UNSW team working with Professor Kohei M. Itoh of Japan Keio University has done just that for the first time.

and turned them into qubits. he silicon chip in your smartphone or tablet already has around one billion transistors on it,

a UNSW Research Fellow and the lead author of the Nature paper. ee morphed those silicon transistors into quantum bits by ensuring that each has only one electron associated with it.

Dzurak noted that the team had recently atented a design for a full-scale quantum computer chip that would allow for millions of our qubits,

the quantum bits (qubits) in a laboratory, control them and use them for simple computations. For practical application, a particular class of quantum computers, the so-called adiabatic quantum computer, has generated recently a lot of interest among researchers and industry.

The problem is encoded in the interaction between qubits; to encode a generic problem, an all-to-all connectivity is necessary,

but the locality of the physical quantum bits limits the available interactions.""The programming language of these systems is the individual interaction between each physical qubit.

The possible input is determined by the hardware. This means that all these approaches face a fundamental challenge

The trio, working at the University of Innsbruck and the IQOQI, suggest overcoming the challenges by detaching the logical qubit from the physical implementation.

Each physical qubit corresponds to one pair of logical qubits and can be tuned by local fields.

These could be electrical fields when dealing with atoms and ions or magnetic fields in superconducting qubits."

the physicists arrange the qubits in a way that four physical qubits interact locally.""In this way we guarantee that only physical solutions are possible,

The solution of the problem is encoded redundantly in the qubits.""With this redundancy our model has also a high fault tolerance,

In an experiment, recently published in Science("Probing Johnson noise and ballistic transport in normal metals with a single-spin qubit),

Like atomic systems, the NV centers can be used as a qubit. In this experiment, physicists harness the sensitivity of these isolated quantum systems to characterize electron motion.

#Electrical control of quantum bits in silicon paves the way to large quantum computers (Nanowerk News) A University of New south wales (UNSW)- led research team has encoded quantum information in silicon using simple electrical pulses for the first time,

The findings were published today in the open-access journal Science Advances("Electrically controlling single-spin qubits in a continuous microwave field".

Unlike conventional computers that store data on transistors and hard drives, quantum computers encode data in the quantum states of microscopic objects called qubits.

& Communication Technology, was first in the world to demonstrate single-atom spin qubits in silicon,

The team has improved already the control of these qubits to an accuracy of above 99%and established the world record for how long quantum information can be stored in the solid state

"We demonstrated that a highly coherent qubit, like the spin of a single phosphorus atom in isotopically enriched silicon,

"Therefore, we can selectively choose which qubit to operate. It's a bit like selecting which radio station we tune to,

"The findings suggest that it would be possible to locally control individual qubits with electric fields in a large-scale quantum computer using only inexpensive voltage generators, rather than the expensive high-frequency microwave sources.

Moreover, this specific type of quantum bit can be manufactured using a similar technology to that employed for the production of everyday computers,

Key to the success of this electrical control method is the placement of the qubits inside a thin layer of specially purified silicon

does not disturb the quantum bit, "Associate professor Morello said. The purified silicon was provided through collaboration with Professor Kohei Itoh from Keio University in Japan n

#A quantum logic gate in silicon built for the for the first time (w/video) The significant advance, by a team at the University of New south wales (UNSW) in Sydney appears today in the international journal Nature("A two-qubit logic gate in silicon"."

"We've demonstrated a two-qubit logic gate-the central building block of a quantum computer-and, significantly, done it in silicon.

0 or 1. However, a quantum bit (or'qubit')can exist in both of these states at once, a condition known as a superposition.

A qubit operation exploits this quantum weirdness by allowing many computations to be performed in parallel (a two-qubit system performs the operation on 4 values, a three-qubit system on 8, and so on."

the ability to conduct one-and two-qubit calculations are said essential Dzurak, who jointly led the team in 2012 who demonstrated the first ever silicon qubit,

also reported in Nature. Until now, it had not been possible to make two quantum bits'talk'to each other

-and thereby create a logic gate-using silicon. But the UNSW team-working with Professor Kohei M. Itoh of Japan's Keio University-has done just that for the first time.

and turned them into qubits.""The silicon chip in your smartphone or tablet already has around one billion transistors on it,

"We've morphed those silicon transistors into quantum bits by ensuring that each has only one electron associated with it.

Dzurak noted that that the team had patented recently a design for a full-scale quantum computer chip that would allow for millions of our qubits,

#Scientists design a full-scale architecture for a quantum computer in silicon Australian scientists have designed a 3d silicon chip architecture based on single atom quantum bits,

and have developed the world's most efficient quantum bits in silicon using either the electron or nuclear spins of single phosphorus atoms.

Quantum bits-or qubits-are the fundamental data components of quantum computers. One of the final hurdles to scaling up to an operational quantum computer is the architecture.

Here it is necessary to figure out how to precisely control multiple qubits in parallel, across an array of many thousands of qubits,

which uses atomic-scale qubits aligned to control lines -which are essentially very narrow wires-inside a 3d design."

and have been working towards a full-scale architecture where we can perform error correction protocols-providing a practical system that can be scaled up to larger numbers of qubits,

"In the team's conceptual design, they have moved from a one-dimensional array of qubits, positioned along a single line,

This qubit layer is sandwiched"in a three-dimensional architecture, between two layers of wires arranged in a grid.

multiple qubits can be controlled in parallel, performing a series of operations using far fewer controls. Importantly, with their design, they can perform the 2d surface code error correction protocols in which any computational errors that creep into the calculation can be corrected faster than they occur."

"Our Australian team has developed the world's best qubits in silicon, "says University of Melbourne Professor Lloyd Hollenberg,

"However, to scale up to a full operational quantum computer we need more than just many of these qubits-we need to be able to control

""In our work, we've developed a blueprint that is unique to our system of qubits in silicon,

needed to address individual qubits, and make the processor work.""This architecture gives us the dense packing

"Ultimately, the structure is scalable to millions of qubits, required for a full-scale quantum processor."

0 or 1. However, a qubit can exist in both of these states at once, a condition known as a superposition.

A qubit operation exploits this quantum weirdness by allowing many computations to be performed in parallel (a two-qubit system performs the operation on 4 values, a three-qubit system on 8, and so on.

a graduate student in the Mazur lab and co-author on the paper. t could also improve entanglement between quantum bits,

The newly developed device allows two quantum bits -or qubits-to communicate and perform calculations together,

which is a crucial requirement for quantum computers. Even better, the researchers have worked also out how to scale the technology up to millions of qubits

which means they now have the ability to build the world's first quantum processor chip and, eventually, the first silicon-based quantum computer.

Qubits, on the other hand, can be in the state of 0, 1, or both at the same time, which gives quantum computers unprecedented processing power...

Scientists are getting pretty good at controlling these qubits, but what they've struggled with is getting them to communicate with each other

in order to get two qubits to'talk'to each other, they have to be incredibly close together-generally within 20 to 40 nanometres of each other

Quantum bits, on the other hand are defined by the spin of a single electron. But by reconfiguring traditional transistors to only be associated with one electron,

Dzurak and his team were able to have them define qubits instead. ee morphed those silicon transistors into quantum bits by ensuring that each has only one electron associated with it.

We then store the binary code of 0 or 1 on the'spin'of the electron,

The team then showed that they could use metal electrodes on these transistors to control the qubits

The researchers have patented already a design"for a full-scale quantum computer chip that would allow for millions of our qubits,

#Electrical control of quantum bits in silicon paves the way to large quantum computers Lead researcher, UNSW Associate professor Andrea Morello from the School of Electrical engineering and Telecommunications, said his team had realised successfully a new control method for future quantum computers.

Unlike conventional computers that store data on transistors and hard drives, quantum computers encode data in the quantum states of microscopic objects called qubits.

was first in the world to demonstrate single-atom spin qubits in silicon, reported in Nature in 2012 and 2013.

The team has improved already the control of these qubits to an accuracy of above 99%and established the world record for how long quantum information can be stored in the solid state,

"We demonstrated that a highly coherent qubit, like the spin of a single phosphorus atom in isotopically enriched silicon,

"Therefore, we can selectively choose which qubit to operate. It's a bit like selecting which radio station we tune to,

"The findings suggest that it would be possible to locally control individual qubits with electric fields in a large-scale quantum computer using only inexpensive voltage generators, rather than the expensive high-frequency microwave sources.

Moreover, this specific type of quantum bit can be manufactured using a similar technology to that employed for the production of everyday computers,

Key to the success of this electrical control method is the placement of the qubits inside a thin layer of specially purified silicon

does not disturb the quantum bit, "Associate professor Morello said. The purified silicon was provided through collaboration with Professor Kohei Itoh from Keio University in Japan n

"We've demonstrated a two-qubit logic gate--the central building block of a quantum computer--and, significantly, done it in silicon.

0 or 1. However, a quantum bit (or'qubit')can exist in both of these states at once, a condition known as a superposition.

A qubit operation exploits this quantum weirdness by allowing many computations to be performed in parallel (a two-qubit system performs the operation on 4 values, a three-qubit system on 8, and so on."

the ability to conduct one-and two-qubit calculations are said essential Dzurak, who jointly led the team in 2012 who demonstrated the first ever silicon qubit,

also reported in Nature. Until now, it had not been possible to make two quantum bits'talk'to each other

--and thereby create a logic gate--using silicon. But the UNSW team--working with Professor Kohei M. Itoh of Japan's Keio University--has done just that for the first time.

and turned them into qubits.""The silicon chip in your smartphone or tablet already has around one billion transistors on it,

"We've morphed those silicon transistors into quantum bits by ensuring that each has only one electron associated with it.

Dzurak noted that that the team had patented recently a design for a full-scale quantum computer chip that would allow for millions of our qubits,

< Back - Next >

Overtext Web Module V3.0 Alpha
Copyright Semantic-Knowledge, 1994-2011