Shruti Puri Wins NSF CAREER Award

Departments: Applied Physics

For her work on developing a more robust quantum computing system, Shruti Puri has won a 2021 Faculty Early Career Development (CAREER) Award from the National Science Foundation (NSF). 

Puri, assistant professor of applied physics, will use the $500,000, five-year grant to develop what’s known as a continuous-variable (CV) or bosonic quantum hardware system that will be more resource-efficient and better at correcting system errors. The NSF CAREER award is a prestigious honor for young faculty members and supports the early career activities of teachers and scholars who are most likely to become the academic leaders of the future.

The project aims to fully harness the power of quantum phenomena by making a fault-tolerant quantum computing. That means that the system reliably executes a quantum algorithm even if some of its constituent hardware components have failed. It is possible to build a fault-tolerant quantum computing architecture, however, the required hardware performance and resources are hard to meet with current technology.  

Puri’s work aims to ease these requirements by using the emerging technology of superconducting continuous-variable (CV) or bosonic qubits in which a bit of quantum information is stored in quantum states of microwave-frequency photons. The quantum states constituting the qubit have large number of photons. At first, this seems counter-productive, since adding more photons also means a higher rate of faults. Importantly, however, if one carefully constructs the states, then these faults can be easily detected and corrected either actively or autonomously. Because there are fewer faults to begin with, it becomes easier to scale up and build a robust computing system in a more efficient manner. Moreover, by engineering the qubit cleverly, it is also possible to ensure that the small amount of remaining faults are of the kind that be easily corrected at the system level. 

When she entered the field of quantum optics and quantum info theory, Puri was surprised by the division between those working on system architecture and those working on hardware. Because they were working separately, it meant that assumptions would have to be made about what kind of errors could potentially happen - assumptions that aren't always accurate. As a result, systems are often designed to protect against a broad range of potential errors - many of which very likely will never happen – leading to an inefficient use of the system’s resources.

Puri’s background allows her to understand the hardware physics and the actual noise in the system, and determine the dominant sources of errors in the system that need to be anticipated and corrected.