When Mohammad Javad Khojasteh arrived at MIT’s Information and Decision Systems Laboratory (LIDS) to start his postdoctoral position in 2020, he was introduced to a whole new universe. The area he knew best could be explained by “classical” physics, which predicts the behavior of ordinary objects with near-perfect accuracy (remember Newton’s three laws of motion). But this new universe has been governed by bizarre laws that can lead to unpredictable results while operating at scales typically smaller than an atom.
“The rules of quantum mechanics are counterintuitive and seem very strange when you first learn them,” says Khojasteh. “But the more you know, the clearer it becomes that the underlying logic is extremely elegant.”
As a member of Professor Moe Win’s lab, dubbed the Wireless Information and Network Sciences Laboratory or WINS Lab, Khojasteh’s mission is to span both the classical and quantum realms to deliver cutting-edge communications, sensing and computational capabilities.
Khojasteh grew up in Iran and knew early on that he wanted to be a scientist. In high school, he was particularly fascinated by physics. He was a first-generation college graduate and earned a dual bachelor’s degree in electrical engineering and mathematics from Sharif University of Technology before completing his PhD in electrical and computer engineering at the University of California, San Diego (UCSD). There he worked at the intersection of robotics and machine learning, developing tools to protect against cyber threats and adaptive planning algorithms for autonomous robots to operate safely in changing real-world scenarios. After graduating from UCSD in 2019, he recalls calling home to break the good news: “Mom, I’m officially a doctor now.”
After a stint at Caltech, where Khojasteh worked with NASA researchers to develop planning and control algorithms to improve off-road autonomous driving and build robots for life-detection missions on other planets, Khojasteh relocated across the country to Cambridge, Massachusetts to join LIDS and the WINS laboratory.
“LIDS has always been at the heart of decision making and information science,” he says. “I remember reading articles and textbooks by LIDS professors as an undergraduate and later as a PhD student, so it was really exciting to get the chance to work with these renowned researchers during my postdoctoral years. LIDS is such an interesting and vibrant environment.”
Up to this point, Khojasteh had mainly focused on classical systems such as autonomous vehicles, although he had always been very interested in quantum systems. In the WINS Lab he was finally able to concentrate on both activities at the same time.
He explains that a quantum revolution is on the horizon that will change the way devices perform sensing, computing and communication tasks. Problems that traditional computers take years to solve will be child’s play for the big quantum computers that are expected to come online in the next few decades. These novel quantum computers will, for example, enable biologists and chemists to better simulate molecular interactions to design new drugs – and even help engineers design better batteries. These machines will also use the laws of quantum physics to advance medical research and clinical care.
In Khojasteh’s words, “This quantum revolution will change lives and help us better understand the world around us.”
Being so new to the field of quantum mechanics when he arrived at the WINS lab, Khojasteh began reading related articles and discussing with his lab colleagues to catch up. In the meantime, he started working on a project related to classical systems that helps robots navigate while keeping their locations secret to prevent potential security breaches.
As Khojasteh began to master the rules of the quantum universe, he took on a second project that has since become his primary concern, which aims to develop data-driven techniques to control the fundamental units of information that power quantum computers.
While classical computers store information as electrical impulses representing ones and zeros called “bits,” quantum computers use quantum bits, or “qubits,” which typically can be subatomic particles. Because of their unique quantum mechanical properties, qubits can represent values other than 0 or 1: they can also represent 0 and 1 simultaneously in different weights (a phenomenon known as superposition, which can lead to computational advantages). However, because the dynamics of quantum systems are so difficult to predict, controlling the state of these qubits is no easy task. While traditional approaches rely on hand-designed models, Khojasteh’s method uses a hierarchical design that overlays exploratory control, quantum tomography, Hamiltonian learning, and data-driven control techniques to fine-tune the dynamics of these qubits and operate quantum computers more efficiently.
“I learned so much from Professor Win,” says Khojasteh. “There are very few research groups that get a foothold in both classical and quantum physics, so working in his lab was an amazing opportunity.”
Almost a year before his postdoc position, Khojasteh started thinking about his next career steps. He plans to apply for research scientist positions in industry as well as faculty positions. Becoming a professor would allow him to continue teaching, which he enjoyed immensely during his time at LIDS. In addition to serving as a teaching assistant, he has also volunteered for MIT’s Summer Research Program (MSRP), which empowers students from historically underrepresented groups in science to become researchers. Khojasteh mentored an MSRP student for over a year, and the two even authored a study together.
Regardless of whether he pursues a career in academia or in industry, Khojasteh would like to continue doing basic research in quantum systems. His interdisciplinary background in physics, mathematics, engineering, robotics, machine learning and quantum mechanics has given him a multi-faceted perspective that he applies to every research problem he encounters.
“I’m someone who likes to cross the imaginary boundaries between fields and try different methods to answer a research question,” he says. “Everyone at LIDS also really appreciates this interdisciplinary approach, which gives them a comprehensive vision to do really interesting research and solve important problems.”