A group of scientists has thrown light into the mysterious particles called Majorana by applying two measurement techniques. The discovery will help reduce interpretation uncertainties in the future search for these elusive particles.
The science and other stuff to know
Majoranas are mysterious, easily overlooked particles and are often mistaken for other quantum states. But a new study published in the journal Nature by scientists at the Institute of Science and Technology Austria (ISTA), the Materials Science Institute in Madrid (ICMM), CSIC, and the Catalan Institute of Nanoscience and Nanotechnology (ICN2) is shedding light into the mystery of Majorana physics.
For the first time ever, researchers applied two techniques simultaneously to a hybrid superconductor-semiconductor nanodevice, the most promising platform for realizing Majoranas.
To their surprise, they found that the states observed with one technique (Coulomb spectroscopy), which is highly suggestive of Majoranas at first glance, weren’t present when looking for them from the different perspective afforded by the second technique (tunneling spectroscopy).
“We aimed to find out how to see if there is a Majorana or not,” researchers said in their paper. “In our experimental conditions, the doors are nothing but tunnel barriers in which electrons are sent in and out. There’s a drain door and a source door. Seen from the two spectroscopy methodologies together at the same time, our Majorana rock star imposter turns out to be another kind of quasi-particle. Don’t get us wrong, these are interesting superconductor quasi-particles, but not Majoranas.”
The new findings suggest convincing Majorana impostors are everywhere. They can exist in different types of devices and can deceive different measurement strategies individually.
Combining two measurement strategies to detect Majoranas revealed the impostor through an apparent paradox, an approach that could drastically reduce interpretation ambiguities of future experiments. This step may one day help scientists trap the elusive Majorana, and finally, begin to harness its power.
Over the past decade, scientists have been studying hybrid superconductor-semiconductor nanodevices, with the hope of unambiguously proving the existence of Majoranas. And this new study proves their existence, opening doors to further research on these quantum particles.