. Now researchers have found that a magnetic field (curved arrows) can switch the amount of heat that flows from a hot side (red) to a cold one (blue).)
Electricity can run between two superconductors even through electrically insulating barriers (yellow). Now researchers have found that a magnetic field (curved arrows) can switch the amount of heat that flows from a hot side (red) to a cold one (blue).
Image: Nature magazine
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The strange world of quantum mechanics just got a little stranger with the discovery that a magnetic field can control the flow of heat from one body to another. First predicted nearly 50 years ago, the effect might some day form the basis of a new generation of electronic devices that use heat rather than charge as the information carrier.
The research stems from the work of physicist Brian Josephson, who in 1962 predicted that electrons could 'tunnel' between two superconductors separated by a thin layer of insulator — a process forbidden in classical physics. The Josephson junction was subsequently built and used to make superconducting quantum interference devices (SQUIDs), which are now sold commercially as ultra-sensitive magnetometers.
In the latest work, Francesco Giazotto and María José Martínez-Pérez at the NEST nanoscience institute in Pisa, Italy, measured the devices’ thermal behavior — that is, how the electrons inside them transfer heat. The duo heated one end of a SQUID several micrometers long and monitored the temperature of an electrode connected to it. A SQUID consists of two y-shaped pieces of superconductor joined together to form a loop, but with two thin pieces of insulating material sandwiched in between (see figure); as the researchers varied the magnetic field passing through the loop, the amount of heat flowing through the device also changed. The effect was in line with a theory put forward by Kazumi Maki and Allan Griffin in 1965.
The device worked by partly reversing the heat transfer, so that some would flow from the colder body to the warmer one. “This is completely unintuitive,” says Giazotto. “People are used to thinking of heat as disorder, so how can you impose quantum order on it? Amazingly, a device with Josephson junctions can do that.”
Legal violation
This apparent violation of the second law of thermodynamics — which states that heat will always flow from a hotter to a colder body — is, in fact, perfectly legal, says Giazotto, because only part of the total heat flow is subject to the phase variation. When you also take into account the heat transferred by single electrons, as occurs inside normal metals, the net flow is still from the hot to the cold end.
Like its electrical counterpart, this variation in the heat flow can be explained in terms of the superconductors’ 'phase' — the position of the peaks and troughs of the wavefunction that describes the superconducting electron pairs in the SQUID’s loop. The greatest heat flow occurs when the peaks inside one half of the loop line up with peaks in the other half, whereas the flow is at a minimum when peaks meet troughs. The magnetic field shifts those phases relative to each other, thus modifying the heat flow.
Teun Klapwijk of the Delft University of Technology in the Netherlands describes Giazotto and Martínez-Pérez's research as “cute” but “not very surprising”. He also doubts that it will have significant practical applications. “The only possible area would be solid-state refrigeration, which would replace cryogenic liquids,” he says.
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Add CommentI knew this would occur when our technology caught up with our theories. Now, mount a bunch of them on a light aluminum frame, put a spindle (like an aircrafts' turbine engines' spindle) and seal it up, except for an intake and exhaust port, and viola; Nothing. Well, it was a thought. We need a small device that runs on rare earth magnetics, with a computer interface, that provide our future power supplies, ie. elec generators, power supplies for our vehicles, our houses, our factories, and any industry that produces anything at a cost of pollution. Until we do, we, as a species, will continue to spoil the water, lakes, rivers, lands, and even the very air we all breathe. How long can our planet sustain life, with population growth, pollution, and a finite food supply? We can only grow so much, and yet there so many people to feed. We build houses, shopping mall, businesses...we're a building people. How large will cities be in the future? Eventually, we'll outgrow our own food supply, and deplete our natural resources. It may sound dismal, but right now, we have it made. We can still breathe the air, we can still drink the water, and we can still consume the foods we grow in the soil. What does the future hold for mankind? Who knows? Could be next week, or next year, or maybe the next century. All we do know is, that mankind will adapt, or perish.
Reply | Report Abuse | Link to thisBRAVO !!! We need more folks who can channel Malthus !!! Keep speaking up and out !!! The future of the planet depends on folks like you !!
Reply | Report Abuse | Link to thisIf Chicken Little's argument is characteristic of optimism for the future, I'm glad I'm old.
Reply | Report Abuse | Link to thisI will certainly try to track down a better, more technical/engineering article of how this is set up and works. I want to build an experiment in my own lab. I don't like trusting a pop new article with how quantum mechanics has once again violated the laws of physics, let alone the laws of lab research that has come before. More later. . .
Reply | Report Abuse | Link to this@pestleman1951: Are you seriously calling imintowater a fool? If so, I disagree.
Reply | Report Abuse | Link to thisEVERY EFFECT THAT MATTER EXHIBITS IS ASCRIBED TO ELECTRICITY AND / OR MAGNETISM OR, ELECTROMAGNETISM .
Reply | Report Abuse | Link to thisTHE COUNTER INTUITIVE BEHAVIOUR OF HEAT ,NORMALLY A DISORGANIZING AGENT but AS AN ORGANIZING AGENT ( in the case of Josephson junction ) Is ASCRIBED TO "QUANTUM EFFECTS" .
Now A NEW DISCIPLINE OF SCIENCE IS BORN, by the name,
"Coherent caloritronics" to rhyme with " electronics" an old trick of material physicists who are good at coining words like "gravitons" to rhyme with " electrons " to create the impression that even gravity could be broken down to it's tiny bits of matter to indicate that all energies are "matter- based", thus attempting to establish the fundamentality of "matter"which it has no right to claim such a unique status
Otherwise,how can anyone think that such an obviously continuous entity as the fabric of "space- time" (or the distortions in it) as discretized energy,as the electrons? .
Physicists had no qualms to quantize another continuous entity as a beam or ray of light, a vain attempt at that , which they covered up by coining another term
" wavicles " , to make continuous waves as discrete particles, to enable the physicists to cope with the dual contradictory nature of radiations that does not fit well with concepts of particles which is the defining quality of matter .
Even in the midst of such unbridgeable differences they would not accept that there are more things fundamental in nature than " matter " .
One such entity is "Life" or BIO- ENERGY ".
Another perhaps is " cold " ( which may not be "absence of heat", because, heat is created by the movement of particles ), and " cold " is the initial state even prior to the appearance of " matter " particles in cosmos .
Cosmos didn't have "matter" , to start with but it was an energy- burst , the vacuum- energy popping out spontaneously without any particular cause or reason..
(continued ) .
(In continuation )
Reply | Report Abuse | Link to thisIn fact " cold" is a continuity whereas "heat" is based on discontinuities .
" cold" is more fundamental than " heat " .
But particle physicists ( or matter- based-energy physicists ) would take a longer time to accept it .
They cannot imagine a universe without particles of matter in it.
Say, for example, a cosmos of "information" ( ie, spontaneously processed awareness ) ,before even quarks or strings or protons and electrons originated , a cosmos where only " awareness " , cosmic awareness , "cold cosmic awareness" which is the fundamental "life- energy" , the basis of bio- energy for which, to manifest in this dimensional universe of matter, a physical material structure is needed.
This causes the confusion that life - energy is an emergent entity emerging out of various configurations of material structure.
( there seems to be an unjustified stigma attached to then term " life- energy " , as once upon a time the concept of élan vital was discredited by main stream physicists . But , so was cosmological constant too discredited by Einstein himself which now is revived due to new ideas originating from quantum science , the science of the Vaster universe bordering on material and non material entities , phenomena and noumena.
To sum up , the more fundamental entities are, " life- energy " and, " cold- energy " , which are manifestations of the " vacuum-energy " or, spontanous random fluctuations in cosmic-vacuum. And, perhaps " matter" is the emergent phenomena !
PS : here is a phenomena of magnetic heating in our domestic kitchen. In an ordinary magnetic induction cooker, we can boil milk or water in a ferromagnetic vessel without the vessel getting heated up at all. Immediately after the milk is boiled ,you can lift the metal vessel with your bare hands . The vessel will become heated only much later when heat in the milk / water, gets conducted into the body of the vessel , as the milk is cooled in the vessel . This phenomena is due to the magnetic eddy currents ( or hysteresis ) heating directly only the contents of the vessel onsted of first heating the vessel itself .
"But particle physicists ( or matter- based-energy physicists ) would take a longer time to accept it .
Reply | Report Abuse | Link to thisThey cannot imagine a universe without particles of matter in it."
That's funny because to imagine any scenario at all is to experience a "universe without particles of matter in it". By that I mean, to imagine is to experience that which is not itself happening (i.e. the laws of physics without them being dictated by matter).
It seems perfectly plausible that someone could create refrigeration by use of semiconductors and electromagnets. Whether or not it can be made economically competitive is another question.
Reply | Report Abuse | Link to thisAll the mumbo jumbo about the theoretical physics behind the process was unnecessary.
This may be relevant to my BPS brain dynamics model because if magnetic fields can control heat transfer, biological temperature gradients may be able to influence magnetic fields controlling both electron flow and electrically neutral particles in a cooperative effort to bring information arriving at DNA/RNA dark baryonic receptor site from n-1 d transfinite sources into phase space synchrony acceptor sites in human premotor cortex as discussed elsewhere. See <http://www.facebook.com/pages/Dr-Angell-O-de-la-Sierra-Esq/187843051348771>
Reply | Report Abuse | Link to thisAre we just before, finding a way to decrease, or reverse Global Warming?
Reply | Report Abuse | Link to this