Manfra of ECE and MSE leads team that contributes to experiments on light-matter interactions

Purdue researchers collaborated in a Rice University-led study detecting a quantum shift that results from the strong coupling of light and an ultra-high mobility two-dimensional electron gas rotating in opposite directions.
A light field rotating in the opposite direction to an orbiting electron still interacts with the electron in a cavity. The influence of resonance on the counter-rotating element defines a quantum shift.

The work, published on April 16 in Nature Photonics, describes a system predicted to go into a new ground state (or state of lowest energy) that physicists could use to study phase transitions and possibly harness for the development of quantum bits for advanced computing. Researchers found that inducing strong coupling of light and matter in the form of a two-dimensional electron gas leads to a quantum interaction of counter-rotating fields called the Bloch-Siegert shift.

“Our collaborators at Rice have developed a method to probe a light-matter system in a way not previously realized,” said Michael Manfra, professor of physics and astronomy who led Purdue’s team. “The combined material, experimental and theoretical advances really pave the way for many new discoveries.”

In order to detect and measure the shift, Rice researchers placed the electron gas in a cavity and coupled it to circularly polarized light. Purdue visiting scholar Geoff Gardner and graduate student Saeed Fallahi fabricated the electron gas in which the Bloch-Siegert shift was observed. The electrons then hybridized with a resonant electromagnetic field to form so-called Landau polaritons.

“It is great fun to participate in a joint effort that combines Rice’s expertise in light-matter coupling with Purdue’s capabilities in materials physics”, said Manfra, whose Station Q Purdue group focuses on several aspects of quantum computing in solid-state systems.

Landau polaritons, studied by Junichiro Kono’s group at Rice, constitute a two-level system driven by a resonant electromagnetic field. Such systems potentially find applications in quantum technologies relevant to quantum computing.

Source: Purdue contributes to experiments on light-matter interactions for potential quantum technology applications