Sometimes discovering new physics requires insane levels of energy. Big gear. Fancy equipment. Countless hours sifting through tons of data.
And then sometimes the right combination of materials can open a door to unseen realms in a space a little bigger than a table.
Take this new kind of Higgs boson parent, for example. It was found hidden in a piece of layered tellurium crystals at room temperature. Unlike its famous cousin, it didn’t take years of smashing particles to spot it either. Just a clever use of some lasers and a trick to unraveling the quantum properties of their photons.
“It’s not every day that you find a new particle on your table,” says Kenneth Burch, a Boston College physicist and co-lead author of the study announcing the particle’s discovery.
Burch and his colleagues saw what is called an axial Higgs mode, a quantum agitation that technically qualifies as a new type of particle.
Like so many discoveries in quantum physics, observing theoretical quantum behaviors in action brings us closer to uncovering potential cracks in the Standard Model and even helps us focus on solving some of the great remaining mysteries.
“Axial Higgs detection has been predicted in high-energy particle physics to explain dark matter,” says Burch.
“However, it has never been observed. Its appearance in a condensed matter system is quite surprising and announces the discovery of a new state of broken symmetry which had not been predicted.”
It’s been 10 years since the Higgs boson was formally identified amid the carnage of particle collisions by researchers at CERN. This not only ended the hunt for the particle, but loosely closed the last box of the Standard Model – the fundamental particle zoo that is the natural complement to bricks and mortar.
With the discovery of the Higgs field, we were finally able to confirm our understanding of how the model’s components gained mass at rest. It was a huge victory for physics, the one we still use to understand the internal mechanics of matter.
While a single Higgs particle exists for just a fraction of a second, it’s a particle in the truest sense, flashing briefly into reality like a discrete excitation in a quantum field.
There are, however, other circumstances in which particles can confer mass. A break in the collective behavior of a surge of electrons called a charge density wave, for example, would do the trick.
This “Frankenstein’s monster” version of Higgs, called Higgs mode, can also appear with traits not seen in its less patchwork cousin, such as a finite degree of angular momentum (or spin).
A spin-1 or axial Higgs mode not only does similar work to the Higgs boson in very specific circumstances, but it (and similar quasiparticles) could provide interesting bases for studying the dark mass of dark matter.
As a quasiparticle, the axial Higgs mode can only be seen emerging from the collective behaviors of a crowd. Spotting it requires knowing its signature amidst a flood of quantum waves, and then having a way to pull it out of the chaos.
By sending perfectly coherent beams of light from two lasers through such material and then monitoring telltale patterns in their alignment, Burch and his team discovered the echo of an axial Higgs mode in layers of tritelluride from rare earth.
“Unlike the extreme conditions typically required to observe new particles, this was done at room temperature in a tabletop experiment where we get quantum mode control by simply changing the polarization of light,” says Burch.
It is possible that many more such particles will emerge from the entanglement of body parts constituting exotic quantum materials. Having a way to easily see their shadows in the light of a laser could reveal a whole litany of new physics.
This research was published in Nature.