Scientists Make A Discovery Which Could Help Build Faster Electronics, New Study Suggests

Scientists have discovered a previously unknown way to transfer heat at the nanoscale level, which may have important implications in the creation of faster, sleeker, and more memory intensive electronics. It may come as a surprise but heat transfer is a process that is responsible for the working of our electronic devices. Controlling the heat transfer process is also a bottleneck for making ones that are faster and more sophisticated. The world of today is revolutionized and shaped by advances in technology, such as smartphones, computers and other electronic devices which changed the way our society functions, communicates and lives. The advances of our society and proliferation of such devices is of course made possible by the advances in the sciences. It is no coincidence that the name Silicon Valley, where many of these technological advances came from, contains the chemical element, Silicon, which serves as the material used to build chips that power electronic devices. The reason why this material is widely used is due to its chemical properties, namely being a semi-conductor, or a material that allows electrical current to flow through the application of heat. This recent discovery of nanoscale heat transfer is significant for the advancement of more sophisticated devices, but before we can understand the science behind the discovery, let’s delve into the basics of heat transfer. 

The beautiful thing about nature is that it has many intricacies, and the process of heat transfer happens to be one of them. It occurs on the microscopic level, where quantum mechanics come into play. It is thought that heat is transferred as a result of the vibrations of atoms in a crystalline lattice, the motions of which release waves. These waves, as we know from quantum mechanics, also travel in particles, and in the case of heat these particles are called phonons. As the motions of atoms in the lattice increases, so does the number of waves or phonons produced. At a first glance it may seem very straightforward and linear - the more vibrations the more energies. While that is true, a caveat is that when different atoms vibrate, they are pushed around against each other in a lattice where they are all interconnected, which produces different energies due to multitude of varying vibrations. It gets even more complex because each wave released due the vibration can superimpose on another to create a new wave, or new phonon, with a different energy. Thus, heat transfer is characterized by chaos and is hard to control. However, heat dissipation and transfer is vital for semi-conductors, such as silicon, because it allows for the electric current to flow, and powers our electronic devices. Thus, in effect controlling the heat transfer process and understanding more about phonons is one of the ways to advance the electronics field. 

While the heat process is complex enough, phonons are thought only to transfer heat through a medium or when objects are in contact, and not in a vacuum or in empty space. However, recent experiments indicate that in fact phonos can transfer heat in a vacuum. This phenomena arises from the quantum mechanical fact that vacuum space is not empty after-all, rather it is filled with particles that constantly being created or destroyed. This is known as quantum fluctuations, which arise due to a central tenant of quantum mechanics, the Heisenberg uncertainty principle, which states that the exact position and momentum of particle cannot be known at a given time. Thus, as a result of this exist virtual particles that vibrate in and out of space. Due to this phenomenon, scientists discovered the Casimir effect, or a force that two neutral atoms exert on each other as separate by a vacuum which is resulting from the vibrations of the virtual particles in vacuum space. However, while it was theorized that it could be applied to phonons, it has not been observed experimentally until most recently by researchers at University of California at Berkley, where the Casimir effect served as the inspiration. These researches experimentally proved that at nanoscale distances phonons can transfer heat due quantum fluctuations. 

As if the process of heat transfer was not chaotic enough, it adds another piece to puzzle and gives scientists another insight into the mechanics of heat transfer. The significance of this is that it will allow us a different avenue of controlling heat transfer by giving scientists a new understanding of the underlying mechanics and caveats of heat transfer, which will help enable to create faster and more efficient computer chips, and as a result devices. It also illustrates an inherent principle in nature, which is lucidly demonstrated in this study: small seemingly innocuous events are often the underlying drivers behind bigger events and discoveries.