Hafezi Research Group

JQI Fellow Mohammad Hafezi has been elected as a Fellow of the American Physical Society (APS). He was cited for “pioneering theoretical and experimental work in topological photonics and quantum synthetic matter.”

On the cover of the Pink Floyd album Dark Side of the Moon, a prism splits a ray of light into all the colors of the rainbow. This multicolored medley, which owes its emergence to the fact that light travels as a wave, is almost always hiding in plain sight; a prism simply reveals that it was there.

Long-range correlated errors can severely impact the performance of NISQ (noisy intermediate-scale quantum) devices, and fault-tolerant quantum computation. Characterizing these errors is important for improving the performance of these devices, via calibration and error correction, and to ensure correct interpretation of the results.

Identical twins might seem “indistinguishable,” but in the quantum world the word takes on a new level of meaning. While identical twins share many traits, the universe treats two indistinguishable quantum particles as intrinsically interchangeable. This opens the door for indistinguishable particles to interact in unique ways—such as in quantum interference—that are needed for quantum computers. While generating a crowd of photons—particles of light—is as easy as flipping a light switch, it’s trickier to make a pair of indistinguishable photons. And it takes yet more work to endow that pair with a quantum mechanical link known as entanglement. JQI researchers and their colleagues describe a new way to make entangled twin particles of light and to tune their properties using a method conveniently housed on a chip, a potential boon for quantum technologies that require a reliable source of well-tailored photon pairs.

The mechanism by which thermodynamics sets the direction of time’s arrow has long fascinated scientists. Here, we show that a machine learning algorithm can learn to discern the direction of time’s arrow when provided with a system’s microscopic trajectory as input. The performance of our algorithm matches fundamental bounds predicted by nonequilibrium statistical mechanics.

The New York-based Simons Foundation will be supporting our group activities for the next five years. Simons Investigator Awards in Mathematics, Physics, Astrophysics and Computer Science support outstanding theoretical scientists in their most productive years, when they are establishing creative new research directions, providing leadership to the field and effectively mentoring junior scientists. Related JQI news. 

Recently, superlattice structures in two-dimensional materials, such as Moire patterns, have drawn wide interests. While most of the pre-existing methods create superlattice in passive ways, we proposed an optical method of shining circularly polarized and spatially periodic laser fields

JQI Fellow Mohammad Hafezi has been named a 2020 Simons Investigator in Physics by the New York-based Simons Foundation. Simons Investigator Awards in Mathematics, Physics, Astrophysics and Computer Science support outstanding theoretical scientists in their most productive years, when they are establishing creative new research directions, providing leadership to the field and effectively mentoring junior scientists.

We proposed a new method for enhancing superconductivity in cuprates via melting the collective fluctuations of the competing orders.