Posted on 02/08/2019 1:11:58 PM PST by ETL
Quantum physics sets the laws that dominate the universe at a small scale. The ability to harness quantum phenomena could lead to machines like quantum computers, which are predicted to perform certain calculations much faster than conventional computers.
One major problem with building quantum processors is that the tracking and controlling quantum systems in real time is a difficult task because quantum systems are overwhelmingly fragile: Manipulating these systems carelessly introduces significant errors in the final result.
New work by a team at Aalto could lead to precise quantum computers.
The researchers report controlling quantum phenomena in a custom-designed electrical circuit called a transmon. Chilling a transmon chip to within a few thousandths of a degree above absolute zero induces a quantum state, and the chip starts to behave like an artificial atom. One of the quantum features that interests researchers is that the energy of the transmon can only take specific values, called energy levels. The energy levels are like steps on a ladder: A person climbing the ladder must occupy a step, and can't hover somewhere between two steps. Likewise, the transmon energy can only occupy the set values of the energy levels. Shining microwaves on the circuit induces the transmon to absorb the energy and climb up the rungs of the ladder.
In work published 8 February in the journal Science Advances, the group from Aalto University led by Docent Sorin Paraoanu, senior university lecturer in the Department of Applied Physics, has made the transmon jump more than one energy level in a single go. Previously, this has been possible only by very gentle and slow adjustments of the microwave signals that control the device. In the new work, an additional microwave control signal shaped in a very specific way allows a fast, precise change of the energy level. Dr. Antti Vepsäläinen, the lead author, says, "We have a saying in Finland: 'hiljaa hyvää tulee' (slowly does it). But we managed to show that by continuously correcting the state of the system, we can drive this process more rapidly and at high fidelity."
Dr. Sergey Danilin, one of the co-authors, describes quantum control—the process of using chips like transmons to build quantum computers—by extending the "climbing a ladder" analogy. "To get a useful quantum system, you need to imagine climbing a ladder while holding a glass of water—it works if one does it smoothly, but if you do it too fast, the water spills. Certainly, this requires a special skill."
The researchers found that in the quantum world, the trick for climbing the ladder quickly without spilling any water is by carefully jumping two rungs at a time. This short-cut up the energy ladder was achieved by making the transmon absorb two microwave photons at the same time. The laws of nature put a restriction on how fast any quantum energy switch can occur, even with short-cuts, a restriction called the "quantum speed limit." To their delight, the Aalto scientists found that their new method resulted in changes to the energy level that took place at speeds that were close to this theoretically calculated limit.
The wider impact of controlling high-speed energy transfers in quantum systems is also exciting to the team. Of potentially high importance are quantum computing and quantum simulation applications, which requires fast and highly robust operations such as state preparation and the creation of quantum gates. Dr. Paraoanu sees other opportunities, as well: "We would like to understand more deeply the processes related to energy transfer, which are ubiquitous in the natural world and in the technology that surround us. For example, are there any fundamental limits to how fast we can charge the battery of an electric car?" In the rapidly developing field of quantum technologies, it is possible that this new control method will find multiple applications.
Explore further: A circuit platform made of strongly interacting microwave photons
More information: "Superadiabatic population transfer in a three-level superconducting circuit" Science Advances (2019). DOI: 10.1126/sciadv.aau5999 , http://advances.sciencemag.org/content/5/2/eaau5999
Journal reference: Science Advances 
Ours is stainless steel, so we have to shine it every day..................
Heisenberg, Schrodinger and Ohm are in a car
They get pulled over. Heisenberg is driving and the cop asks him “Do you know how fast you were going?”
“No, but I know exactly where I am” Heisenberg replies.
The cop says “You were doing 55 in a 35.” Heisenberg throws up his hands and shouts “Great! Now I’m lost!”
The cop thinks this is suspicious and orders him to pop open the trunk. He checks it out and says “Do you know you have a dead cat back here?”
“We do now, asshole!” shouts Schrodinger.
The cop moves to arrest them. Ohm resists.
Things behave strangely at fractions of a Kelvin. There's very little energy involved in atomic or molecular motion there.
One night when his charge was pretty high, Micro-Farad decided to seek out a cute coil to let him discharge. He picked up Milli-Amp and took her for a ride on his Megacycle. They rode across the Wheatstone Bridge, around the sine waves, and stopped in the magnetic field by a flowing current. Micro-Farad, attracted by Milli-Amp's characteristic curves, soon had her fully charged and excited her resistance to a minimum. He laid her on the ground potential, raised her frequency, and lowered her reluctance. He pulled out his high voltage probe and inserted it in her socket, connecting them in parallel and began short circuiting her resistance shunt. Fully excited, Milli-Amp mumbled, "OHM-OHM-OHM." With his tube operating at a maximum and her field vibrating with his current flow, it caused her shunt to overheat, and Micro-Farad was rapidly discharged and drained off every electron. They fluxed all night trying various connections and sockets until his magnet had a soft core and lost all of its field strength. Afterwards, Milli-Amp tried self-induction and damaged her solenoids. With his battery fully discharged, Micro-Farad was unable to excite his field, so they spent the rest of the night reversing polarity and blowing each other's fuses.
“We would like to understand more deeply the processes related to energy transfer, which are ubiquitous in the natural world and in the technology that surround us. For example, are there any fundamental limits to how fast we can charge the battery of an electric car?”
Wrong way. The human brain works with little energy compared to computers. Forget silicon go carbon based.
Absolute zero is the lowest limit of the thermodynamic temperature scale, a state at which the enthalpy and entropy of a cooled ideal gas reach their minimum value, taken as 0.
The fundamental particles of nature have minimum vibrational motion, retaining only quantum mechanical, zero-point energy-induced particle motion.
The theoretical temperature is determined by extrapolating the ideal gas law; by international agreement, absolute zero is taken as -273.15 deg on the Celsius scale (International System of Units),[1][2] which equals -459.67 deg on the Fahrenheit scale (United States customary units or Imperial units).[3]
The corresponding Kelvin and Rankine temperature scales set their zero points at absolute zero by definition.
It is commonly thought of as the lowest temperature possible, but it is not the lowest enthalpy state possible, because all real substances begin to depart from the ideal gas when cooled as they approach the change of state to liquid, and then to solid; and the sum of the enthalpy of vaporization (gas to liquid) and enthalpy of fusion (liquid to solid) exceeds the ideal gas’s change in enthalpy to absolute zero.
In the quantum-mechanical description, matter (solid) at absolute zero is in its ground state, the point of lowest internal energy.
The laws of thermodynamics indicate that absolute zero cannot be reached using only thermodynamic means, because the temperature of the substance being cooled approaches the temperature of the cooling agent asymptotically,[4] and a system at absolute zero still possesses quantum mechanical zero-point energy, the energy of its ground state at absolute zero. The kinetic energy of the ground state cannot be removed.
Scientists and technologists routinely achieve temperatures close to absolute zero, where matter exhibits quantum effects such as superconductivity and superfluidity.
LOL
Click It!
i can’t jump two steps at time anymore
Heh.
The laws of thermodynamics indicate that absolute zero cannot be reached using only thermodynamic means, because the temperature of the substance being cooled approaches the temperature of the cooling agent asymptotically.....
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Ocasio Cortez tried to patiently explain all that to some professors when she was bartending. They couldn’t get most of it.
The part all agreed on: “So like where do you think we get our electrical power? It comes out of sockets. You plug in and it’s there. No need for power plants, nukes, coal, hydro turbines or any of that jazz. Dismantle them all. If you can’t figure out power comes from a wall socket then I can’t help you. Like, duh.”
Was everything in the explicate universe contained within the implicate universe?
Just askin’.
You guys lost me a couple of lines in. Glad someday is still intelligent.
That is a CLASSIC.
“Manipulating these systems carelessly introduces significant errors in the final result.”
Sounds taylor made for feminist or common core math.
BTTT.
Hahaha, great joke.
Sounds closer to the concept that monitoring the activity of an object interferes with it's activity.
The Chinese have had so they claim quantum computers and are using them to communicate with some of their satellites ... those transmissions cannot be intercepted or decrypted, they say.
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