While conventional electronics use the charge of an electron to transmit a signal, this new technique takes advantage of “spin,” which is a magnetic property of an electron. Previously, creating a circuit using a magnetic insulator was considered impossible because it was impossible to generate strong enough spin waves—perturbations in the magnetic properties of a material caused by an electron with an opposite spin.
Now, instead of trying to generate new spin waves, the researchers tweaked the circuit’s geometry and took advantage of the spin waves that are already present in the material due to thermal fluctuations. They found that when the spin is transferred, heat is also transferred. The researchers concluded that you can heat or cool a circuit by controlling the direction of the magnetization. This new technique could be used to create more efficient integrated circuits in the future.