Atomically-Thin Layer of Hexagonal Boron Nitride

Science Behind the Image

A single atomically-thin layer of hexagonal boron nitride shows that thinner is better with regards to radio-frequency switching applications.

Hexagonal boron nitride (hBN) has a large bandgap, high phonon energies, and an atomically smooth surface absent of dangling bonds. As a result, it has been widely used as a dielectric to investigate electron physics in two-dimensional heterostructures and as a dielectric in the fabrication of two-dimensional transistors and optoelectronic devices.

Here we show that hBN can be used to create analogue switches for applications in communication systems across radio, 5G, and terahertz frequencies. Our approach relies on the non-volatile resistive switching capabilities of atomically thin hBN. The switches are composed of monolayer hBN sandwiched between two gold electrodes and exhibit a cutoff-frequency figure of merit of around 129 THz with a low insertion loss (≤0.5 dB) and high isolation (≥10 dB) from 0.1 to 200 GHz, as well as a high power handling (around 20 dBm) and nanosecond switching speeds, metrics that are superior to those of existing solid-state switches. Furthermore, the switches are 50 times more efficient than other non-volatile switches in terms of a d.c. energy-consumption metric, which is an important consideration for ubiquitous mobile systems. We also illustrate the potential of the hBN switches in a communication system with an 8.5 Gbit s–1 data transmission rate at 100 GHz with a low bit error rate under 10−10.

Visualization Behind the Image

The assembly was rendered using Autodesk Maya with some textures created with photography and edited in Photoshop. Some effects were created in post using Adobe Photoshop.



Jo Wozniak