Specifically designed transistors enable researchers to ‘hear’ defects in a promising nanomaterial

A world analysis workforce led by NYU Tandon Faculty of Engineering and KAIST (Korea Superior Institute of Science and Expertise) has pioneered a brand new approach to determine and characterize atomic-scale defects in hexagonal boron nitride (hBN), a two-dimensional (2D) materials typically dubbed “white graphene” for its exceptional properties.

This advance may speed up the event of next-generation electronics and quantum applied sciences.

The workforce reported that it was capable of detect the presence of particular person carbon atoms changing boron atoms in hBN crystals. This discovery was made potential by listening to the digital “noise” in specifically designed transistors, akin to listening to a whisper in a quiet room.

The analysis is revealed within the journal ACS Nano, which chosen the analysis paper as its cowl story for the October 22, 2024 version.

“On this venture, we primarily created a stethoscope for 2D supplies,” stated Davood Shahrjerdi, one of many paper’s corresponding authors, together with Yong-Hoon Kim. “By analyzing the tiny and rhythmic fluctuations in electrical present, we will ‘understand’ the conduct of single atomic defects.”

Shahrjerdi is an affiliate professor in NYU Tandon’s Electrical and Pc Engineering Division, a school member of NYU WIRELESS, and the Director of the NYU Nanofabrication Cleanroom (NanoFab) that opened in 2023. Kim is Professor of Electrical Engineering at KAIST. Shahrjerdi and Kim are additionally affiliated school at NYU-KAIST International Innovation and Analysis Institute, the place they lead collaborations within the NYU-KAIST Subsequent-Gen Semiconductor Gadgets and Chips analysis group.

The NYU-KAIST partnership was formally launched at NYU in September 2022 by the President of South Korea. This historic partnership combines the distinctive strengths of each universities to drive advances in analysis and training and at the moment includes over 200 school from each establishments.

Single-crystal hBN has emerged as a surprise materials in scientific circles, promising to rework fields from unconventional electronics to quantum applied sciences.

hBN’s atomically skinny construction and glorious insulating properties make it a really perfect medium for internet hosting unique bodily phenomena that aren’t potential with typical supplies. The atomic defects in hBN can degrade its digital properties, generally in ways in which might be harnessed for quantum applied sciences.

The NYU workforce constructed a transistor utilizing a few-layer skinny molybdenum disulfide (one other 2D semiconducting materials) sandwiched between layers of hBN. By cooling this machine to cryogenic temperatures and making use of exact electrical voltages, they had been capable of observe discrete jumps within the present flowing by way of the transistor.

These jumps, referred to as random telegraph alerts (RTS), happen when electrons are captured and launched by defects within the hBN. By rigorously analyzing these alerts at totally different temperatures and voltages, the workforce was capable of decide the power ranges and spatial areas of the defects.

“It is like we have developed a microscope that may ‘see’ particular person atoms, however as a substitute of sunshine, we’re utilizing electrical energy,” stated Zhujun Huang, the paper’s first creator who was an NYU Tandon ECE Ph.D. scholar on the time of the research.

The KAIST workforce then used superior laptop simulations to make clear the atomistic origins of the experimental observations. Particularly, this mixture of experiment and idea revealed that the defects are carbon atoms sitting in locations the place boron atoms must be within the hBN crystal construction.

“Understanding and controlling the defects in 2D supplies may have vital implications for the way forward for electronics and quantum applied sciences,” defined Sharhrjerdi and Kim. “For instance, we’d be capable of create extra good quantum materials platforms for discovery of recent physics or single-photon emitters for safe communications.”

This work provides to NYU Tandon’s increasing portfolio in quantum supplies and machine applied sciences, aligning with the CHIPS and Science Act’s semiconductor innovation targets. Prior analysis demonstrated nanomanufacturing ideas for low-disorder quantum supplies and their potential in units when built-in with superconductors.