Research Highlights

There are many methods to determine what the limits are for certain processes. Many of these methods look to reach the upper and lower bounds to identify them for making accurate measurements and calculations. In the growing field of quantum sensing, these limits have yet to be found.  That may change, thanks to research done by JILA Fellow Graeme Smith and his research team, with JILA and NIST Fellow James Thompson In a new study published in Physical Review Applied, the JILA and NIST researchers collaborated with scientists at the quantum company Quantinuum (previously Honeywell Quantum Solutions) to try and identify the upper limits of quantum sensing.

Physicists study many forms of communication, including quantum communication. Thanks to specific properties of quantum mechanics, like entanglement, information integrity can be better maintained with quantum communications, even being hackproof in some cases. Quantum entanglement is the property that allows two molecules, each in a random quantum state, to be in perfect harmony with each other. This is important, as one common test of quantum communication devices, a.k.a., quantum channels, is to send entangled photons (light particles) down these channels. Entanglement helps when photons are lost or absorbed, as the redundancy in information being sent this way ensures that some of the information will still reach the receiver. 

Quantum channels have their own quirks that make them unique to study. In a new paper published in Nature Communications, post-doctoral researcher Vikesh Siddhu of JILA Fellow Graeme Smith's team looked at some of the logistics in using quantum channels to send information. Siddhu analyzed how noise occurring in a quantum channel affects the information it communicates.

Could quantum entanglement improve our cell phone networks? The Graeme Smith Group at JILA found the answer by playing mathematical logic games.

Quantum computers are set to revolutionize society. With their expansive power and speed, quantum computers could reduce today’s impossibly complex problems, like artificial intelligence and weather forecasts, to mere algorithms. But as revolutionary as the quantum computer will be, its promises will be stifled without the right connections. Peter Burns, a JILA graduate student in the Lehnert/Regal lab, likens this stifle to a world without Wi-Fi.  

When Steven Spielberg’s adorable extra-terrestrial, E. T., wanted to phone home, he should have contacted an information theorist like JILA’s Graeme Smith. Smith could have at least explained how E. T. could have used a cell phone to send a low-noise message to a cell phone tower,¹ and from there––well to outer space (which is a problem that's much, much harder to solve than cell phone to cell phone tower transmissions).