A new device the width of a human hair could help study the physics of light

Physicists have created a tiny device made of a special material called a photonic topological insulator. The device can help study the basic properties of matter and light.

Understanding such details, scientists say, could also lead to the development of more efficient lasers for use in medicine and manufacturing.

The study was published in Nanotechnology of nature.

Topological insulators are materials that do not allow electric current to flow inside, conducting current on the surface of the material. AND photonic A topological insulator works in a similar way, except that instead of current, it only allows photons – light particles – to move on its surface.

Using this property, physicists can use the material to create a quantum simulator – a device in which quantum effects can be studied.

“The photonic topological insulator we created is unique,” ​​says Wei Bao, an assistant professor at New York’s Rensselaer Polytechnic Institute (RPI). “It works at room temperature. This is great progress. Previously, this regime could only be studied using large, expensive equipment that supercools matter in a vacuum.”

“It is also a promising step forward in the development of lasers that require less energy to operate, because our device’s room temperature threshold – the amount of energy needed for its operation – is 7 times lower than previously developed low-temperature devices,” adds Bao.

The device is made of halide perovskite, a crystal composed of cesium, lead and chlorine, and a polymer etched in a pattern on top of the lab-grown crystal.

The crystal and polymer plates were then sandwiched between sheets of different oxide materials. The product is an object only about 2 micrometers thick and 100 micrometers in diameter. This makes it about as thick as a red blood cell.

Shining a laser at the device revealed a glowing triangular pattern, a result of the topological nature of the material.

“The ability to study quantum phenomena at room temperature is an exciting prospect,” says Shekhar Garde, dean of the RPI School of Engineering. “Professor Bao’s innovative work shows how materials science can help us answer some of science’s most important questions.”