Building a “Quantum Heat Pump” To Search For Elusive Dark Matter
Scientists have developed a heat pump that uses light particles on a quantum range. Scientists can currently measure radio frequency signals closer to the quantum limit. Professionals say this technique works in searching for dark matter, a component of the universe whose existence is discernible primarily by its gravitational attraction. 30.1 percent of the universe is composed of dark matter.
A quantum range heat pump made from light particles has been constructed by physicists at TU Delft, ETH Zürich, and the College of Tübingen.
When you blend two objects of different temperatures, such as a warm glass of wine and a chilled pack, warm usually flows from the warm object (the wine) to the cold object (the chill pack). The 2 will eventually reach the same temperature, a procedure called equilibrium in physics: one balance between warm flow in one direction and heat circulation in the other.
It is feasible to break the balance and cause the heat to flow the “incorrect” way by doing some work. Your fridge, for example, uses this concept to maintain your food cold, and heat pumps can utilize it to heat your house by stealing heat from the cold air outside.
Using photons as elementary quantum light particles, Gary Steele and his co-authors demonstrate one quantum equivalent of a warm pump by moving them from a hot to a chilly object “against the flow.”
Previously, the researchers utilized their device as a cold bath for warm radio-frequency photons, but now they are using it as an amplifier simultaneously.
This device can detect superhigh frequency better because of the amplifier built-in, just as superconducting quantum processors can spot microwave signals better when amplified.
We can measure superhigh frequency signals closer to the quantum limitations, which is very exciting because radio frequency signals are challenging to measure elsewhere.
“This new measuring device might have lots of applications, one of them being to look for dark matter,” Steele states.
According to their paper, the tool is called a photon pressure circuit. It comprises superconducting inductors and capacitors on a silicon chip with a temperature of a few millidegrees over absolute zero.
Although this seems extremely cold, for some photons in the circuit, this temperature is hot, and they are excited by the thermal energy.
In previous experiments, scientists have used photon pressure to couple thrilled photons to cold photons of greater frequency, allowing them to cool hot photons into their quantum ground state.
This current work introduces a new twist: by including an extra signal to the cold circuit, the authors can create an amplifying motor that heats the cold photons.
As a result, the additional signal “pump” the photons between the 2 circuits preferentially in one direction. It is possible to cool photons in one part of the circuit to a temperature that is colder than the other part of the circuit by pressing photons a lot more forcefully in one direction than the other. This develops a quantum version of a superconducting heat pump for photons.
Read the original article on curiosmos.
