2022 Recap from Columbia Quantum's Highly Cited Researchers

Seven Columbia Quantum Initiative researchers made Clarivate’s Highly Cited Researcher list this year. Here are a few highlights from 2022.

Ellen Neff
November 23, 2022
Illustration of waveguiding through a crystal lattice

When we encounter metals in our day-to-day lives, we perceive them as shiny. That’s because common metallic materials are reflective at visible light wavelengths and will bounce back any light that strikes them. While metals are well suited to conducting electricity and heat, they aren’t typically thought of as a means to conduct light.

But in the burgeoning field of quantum materials, researchers are increasingly finding examples that challenge expectations about how things should behave. In new research published in Science Advances, a team led by Dmitri Basov describes a metal capable of conducting light through it. 

Read More: Columbia Physicists See Light Waves Moving Through a Metal

​​​​​Cory Dean: Crossover between strongly coupled and weakly coupled exciton superfluids

Two sheets of graphene with cones meeting in between to represent the formation of a bosonic pair.

In theory, superconductivity is the result of paired electrons. In most materials, however, that pairing is weak—two negatively charged particles don’t normally want to pair with each other—and the strength is fixed. In a new article in Science, Cory Dean and collaborators describe an adjustable, graphene-based platform that uses opposite charges—electrons and holes—to form quantum particle pairs under strong magnetic fields. The team can now vary the strength of that pairing along a continuum, which will allow them to test theoretical predictions about the origins of quantum condensates and how they might increase the temperature limits of superconductivity.

Read More: Tuning the Bonds of Paired Particles

Alexander Gaeta: Picosecond-resolution single-photon time lens for temporal mode quantum processing 

A magnifying glass "magnifying" a photon from a laser beam

Light has long been used to transmit information in many of our everyday electronic devices. Because light is made of quantum particles called photons, it will also play an important role in information processing in the coming generation of quantum devices. But first, researchers need to gain control of individual photons. Writing in Optica, Alexander Gaeta and his team propose using a time lens.

Read More: Processing Photons in Picoseconds

James Hone: Dissipation-enabled hydrodynamic conductivity in a tunable bandgap semiconductor

Graphene lattice overlaid with water and red and blue balls representing electrons flowing around obstacles.

You don’t normally want to mix electricity and water, but electricity behaving like water has the potential to improve electronic devices. Recent work from James Hone and colleagues builds new understanding of this unusual hydrodynamic behavior that changes some old assumptions about the physics of metals. The study was published in the journal Science Advances.

Read More: Researchers Explore Hydrodynamic Semiconductor Where Electrons Flow Like Water

Michal Lipson: The revolution of silicon photonics

 Image of a chip used for nonlinear photonics and consisting of hundreds of devices.

In Nature Materials, Michal Lipson comments on two decades of innovation in silicon photonics research, a platform enabling novel research fields and novel applications ranging from remote sensing to ultrahigh-bandwidth communications.

Nanfang Yu: Multifunctional resonant wavefront-shaping meta-optics based on multilayer and multi-perturbation nonlocal metasurfaces

Headset using optical glass

Led by Nanfang Yu, a team has created a flat optical device that focuses only a few selected narrowband colors of light while remaining transparent to nonselected light over the vast majority of the spectrum. The paper was published by Light: Science & Applications. 

“We’ve built a very cool flat optical device that appears entirely transparent—like a simple piece of glass—until you shine a beam of light with the correct wavelength onto it, when the device suddenly turns into a lens,” said Yu.

Read More: Optical Magic

Xiaoyang Zhu: Exciton-coupled coherent magnons in a 2D semiconductor

Illustration of magnons from a lattice.

Magnons have enormous potential, but they are often difficult to detect without bulky pieces of lab equipment. Such setups are fine for conducting experiments, but not for developing devices, said Xiaoyang Zhu, such as magnonic devices and so-called spintronics. Seeing magnons can be made much simpler, however, with the right material: a magnetic semiconductor called chromium sulfide bromide (CrSBr).

In a new article in Nature, Zhu and collaborators how that magnons in CrSBr can pair up with another quasiparticle called an exciton, which emits light, offering the researchers a means to “see” the spinning quasiparticle.

Read More: Scientists See Spins in a 2D Magnet