A world analysis workforce led by NYU Tandon College of Engineering and KAIST (Korea Superior Institute of Science and Know-how) has pioneered a brand new approach to establish 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 in a position to detect the presence of particular person carbon atoms changing boron atoms in hBN crystals. This discovery was made doable by listening to the digital “noise” in specifically designed transistors, akin to listening to a whisper in a quiet room.
ACS Nano chosen the analysis paper as its cowl story for the October 22, 2024 version.
“On this venture, we basically created a stethoscope for 2D supplies,” mentioned 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 are able to ‘understand’ the habits of single atomic defects.”
Shahrjerdi is an affiliate professor in NYU Tandon’s Electrical and Pc Engineering Division, a college 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 World 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 schooling 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 remodel fields from unconventional electronics to quantum applied sciences.
hBN’s atomically skinny construction and wonderful insulating properties make it a great medium for internet hosting unique bodily phenomena that aren’t doable with standard 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 gadget to cryogenic temperatures and making use of exact electrical voltages, they had been in a position to observe discrete jumps within the present flowing by means of the transistor.
These jumps, referred to as random telegraph indicators (RTS), happen when electrons are captured and launched by defects within the hBN. By fastidiously analyzing these indicators at totally different temperatures and voltages, the workforce was in a position to 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,” mentioned Zhujun Huang, the paper’s first creator who was an NYU Tandon ECE Ph.D. pupil on the time of the examine.
The KAIST workforce then used superior laptop simulations to make clear the atomistic origins of the experimental observations. Particularly, this mix of experiment and idea revealed that the defects are carbon atoms sitting in locations the place boron atoms needs to 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 would be capable of create extra excellent quantum materials platforms for discovery of recent physics or single-photon emitters for safe communications.”
