Hello, Mars? Quantum Device Could Help Open Communications

SCIENTISTS ENDEAVOR to put humans on Mars within two decades. Elon Musk wants to build a colony there. Jack Postlewaite, a UMD electrical engineering doctoral student researching deep space communications, envisions a day when Red Planet dwellers could stream “Good Morning America.”

Working in the lab of Clark Distinguished Chair Professor of Electrical and Computer Engineering Saikat Guha, Postlewaite has helped build a laser receiver, the “Green Machine,” that leverages quantum mechanics to extract light particles from extremely faint laser signals like those beamed from faraway satellites.

Converting these photons into coherent communication—not just GMA, but critical information to support Mars habitation—gets increasingly difficult as distance grows. The team, with funding from NASA, used a technique envisioned by Guha to achieve “superadditive capacity” to decode light-starved transmissions. Led by Assistant Research Scientist Chaohan Cui, the group presented the technology in April in Nature Communications.

NASA has increasingly experimented with laser communication, which uses less energy and bandwidth than radio frequency transmission. Scientists in 2023 used lasers to stream a 15-second cat video at broadband speed from 19 million miles away. The distance to Mars, by comparison, is 146 million miles—necessitating the souped-up quantum approach.

“Imagine you have a doctor on Mars who does an MRI scan, and you want to send it to Earth,” says Postlewaite, the study’s co-lead author. “That’s a big file.”