appConfigEntityId

bodyType

customContents

entityId

entityUuid

isVideo

articlePageQuery

article

articleSchemaContent

content

hooksArticlePageAdvertisementConfigArticle

hooksArticlePageFloatingButtonConfigArticle

appConfig

filter

json

liveArticle

Zhang Tong

Graphite has long been a workhorse of industry – used in pencils since the 1500s, in steelmaking during the 1800s, and today in battery electrodes.
Research from Peking University now suggests it could even play a role in next-generation quantum computers.
According to a paper published on July 23 by the peer-reviewed journal Science, the research team has cleared a major obstacle on the road to practical quantum computers and come up with a realistic platform for the production of graphene-based quantum chips.
The team, led by Liu Kaihui, was able to fabricate a long-sought-after form of graphene – the building block of graphite – known as rhombohedral graphene, at a purity and size that had been unachievable until now, the paper said.
Rhombohedral graphene is prized for its ability to host exotic quantum states but until now has been too unstable to produce at scale.
Zhang Zhibin, a co-first author of the paper, said in an interview that previously the only way to obtain the material was through mechanical exfoliation.
“Basically peeling off flakes with tape and then hunting under a microscope for the rare few that happened to have the right stacking, which made up less than 1 per cent of the samples,” he said.


In ordinary graphite, multiple layers of graphene are stacked in a staggered, left-right pattern known as AB stacking. For more than a century, most scientific studies of graphite and graphene focused on this conventional structure.
In 2018, a US team led by Cao Yuan found that twisting two graphene layers at a specific “magic angle” of about 1.08 degrees gave rise to strongly correlated electronic states, producing effects similar to high-temperature superconductivity.
In recent years, scientists have come up with a different stacking arrangement called rhombohedral or ABC stacking, which exhibits properties similar to those of magic-angle graphene, while avoiding the strict requirement for precise rotational alignment.
In this structure, every three layers form a repeating cycle, with each layer shifted in the same direction relative to the one below.
This simple change gives rise to remarkable properties – rhombohedral graphene has been found to exhibit superconductivity and the quantum anomalous Hall effect, in which electrons can move at millimetre-scale distances without losing energy.
That makes it an ideal platform for exploring quantum effects and scientists hope to use it to build topological qubits, a type of quantum computing unit that is largely immune to noise.
The catch is that rhombohedral stacking is unstable and extremely rare in nature. In the laboratory, ABC-stacked graphene tends to spontaneously revert to the more common AB form.
Liu and his team have long worked on making two-dimensional materials. To induce sliding between layers, the simplest approach is to push from the side.
So the team designed a growth template with a step on its edge, allowing graphene to stack layer by layer like building blocks, with the step imposing a geometric boundary that locks in a stable interlayer shift.


After theoretical screening and repeated experiments, the researchers settled on a specific combination: a copper-nickel alloy on an aluminium oxide step, with the alloy serving as both catalyst and epitaxial template.
They found that at high temperatures, carbon atoms formed stable rhombohedral graphene at the interface between the two.
“The samples we produced are over 99 per cent pure, with maximum dimensions of 160 by 80 micrometres and thickness up to 120 nanometres,” Liu said. “We can tune the number of layers from several dozen to several hundred as needed.”
“Our approach establishes a paradigm for stacking-sequence engineering in emergent quantum materials and paves the way for their scalable applications in future quantum science and technologies.”
According to Liu, the material offers “an excellent platform for studying quantum phenomena and, compared to similar materials, it is abundant and easy to process”.
“We can’t predict how far this material will go, but material preparation is the foundation for further research. If future applications emerge, we’ll be ready to build the next generation of quantum devices.”
Three years ago, Liu’s team achieved wafer-scale production of another two-dimensional material, molybdenum disulphide, seen as a candidate for next-generation computing chips that could be faster and more energy-efficient than traditional silicon-based ones.
Looking at the broader field, Liu is optimistic. “Two-dimensional materials already have mature applications in acoustic films and thermal conductors for lithography machines,” he said.
“In chips, while we haven’t seen large-scale replacement of silicon or silicon carbide, there is growing research into integrating 2D materials into the most critical parts – like the most energy-hungry sections of AI chips or the highest-density areas of memory chips – to leverage their unique advantages.”
According to the study’s co-first author Zhao Mengze, the team’s next plan is to stitch together smaller pieces of graphene to achieve even larger sizes.
Passionate about science? Dive deeper with the Dark Matters newsletter, a weekly in-depth analysis on China’s rise in science, technology and military that goes beneath the surface. Sign up for free now.


T. rex was warm-blooded and had body temperature close to ours, study finds

China uses 100,000 home-grown AI chips to build leading weather forecast system

Geologists find unexpectedly large water sources in Xinjiang beneath China’s largest desert

Chinese scientists build world’s smallest CT scanner, weighing just 6kg

Science

Chinese breakthrough paves way for production of graphene-based quantum chips

A simple change to the stacking arrangement of graphene layers gives rise to remarkable properties. Photo: Shutterstock

China’s optical chip breakthrough boosts AI speed 100-fold using fraction of compute power

As AI models permeate ever more applications, the industry’s appetite for computational power has grown insatiable. Photo: Shutterstock

Fields Medallists highlight new wave of Chinese scientists leading global research

Deng Yu (far left) and Wang Hong (far right) were awarded the Fields Medals on Thursday, marking the first time Chinese mathematicians have won the honour. The other recipients for 2026 are American John Pardon (second left) and Canada’s Jacob Tsimerman. Photo: Xinhua

Founder of Moonshot AI, Yang Zhilin. Photo: Reuters

Professor Yau Shing-tung, director of the Yau Mathematical Sciences Centre at Tsinghua University. Photo: Edmond So

Liu Yifeng. Photo: Handout

Shenzhen-based AI mathematician Yurii Nesterov wins top prize in applied maths

Shenzhen-based AI mathematician Yurii Nesterov has won the highest honour in the global applied mathematics community – the Carl Friedrich Gauss Prize. Photo: Handout

Yurii Nesterov is a winner of the Carl Friedrich Gauss Prize. Photo: Handout

Award-winning chemist Zhang Wei leaves US to join China’s Great Bay University

Zhang Wei’s research covers topics from two-dimensional materials and porous organic materials, to sustainable and recyclable polymers, molecular separation and carbon capture. Photo:  Handout

Zhang Wei (left) was presented with an appointment letter by GBU president Tian Gang on July 2. Photo: Handout

News

China

Researchers overcome instability problem of a rare form of the material long prized for its remarkable properties


Researchers overcome instability problem of a rare form of the material long prized for its remarkable properties.


Peking University

Chinese breakthrough paves way for production of graphene-based quantum chips

.css-1c6uqr6{color:inherit;font-weight:inherit;font-size:inherit;font-family:inherit;line-height:inherit;overflow-wrap:break-word;}Researchers overcome instability problem of a rare form of the material long prized for its remarkable properties

Researchers overcome instability problem of a rare form of the material long prized for its remarkable properties