Kirigami (also called "paper-cuts" or "jianzhi") is one of the most traditional Chinese folk arts. It is widely used in window decorations, gift cards, festivals, and ceremonies, etc. Kirigami involves cutting and folding flat objects into 3D shapes. Recently, the techniques of this ancient art have been used in various scientific and technological fields, including designs for solar arrays, biomedical devices and micro-/nano- electromechanical systems (MEMS/NEMS).
Dr. LI Jiafang, from the Institute of Physics (IOP), Chinese Academy of Sciences, has recently formed an international team to apply kirigami techniques to advanced 3D nanofabrication.
Macroscopic paper-cuts in a paper sheet and nano-kirigami in an 80-nm thick gold film.
Credit: Institute of Physics
Inspired by a traditional Chinese kirigami design called "pulling flower," the team developed a direct nano-kirigami method to work with flat films at the nanoscale. They utilized a focused ion beam (FIB) instead of knives/scissors to cut a precise pattern in a free-standing gold nanofilm, then used the same FIB, instead of hands, to gradually "pull" the nanopattern into a complex 3D shape.
The "pulling" forces were induced by heterogeneous vacancies (introducing tensile stress) and the implanted ions (introducing compressive stress) within the gold nanofilm during FIB irradiation.
By utilizing the topography-guided stress equilibrium within the nanofilm, versatile 3D shape transformations such as upward buckling, downward bending, complex rotation and twisting of nanostructures were precisely achieved.
While previous attempts to create functional kirigami devices have used complicated sequential procedures and have been primarily aimed at realizing mechanical rather than optical functions, this new nano-kirigami method, in contrast, can be implemented in a single fabrication step and could be used to perform a number of optical functions.
For a proof-of-concept demonstration, the team produced a 3D pinwheel-like structure with giant optical chirality. The nanodevice achieved efficient manipulation of "left-handed" and "right-handed" circularly polarized light and exhibited strong uniaxial optical rotation effects in telecommunication wavelengths.
In this way, the team demonstrated a multidisciplinary connection between the two fields of nanomechanics and nanophotonics. This may represent a brand new direction for emerging kirigami research.
The team also developed a theoretical model to elucidate the dynamics during the nano-kirigami fabrication. This is of great significance since it allows researchers to design 3D nanogeometries based on desired optical functionalities. In contrast, previous studies relied heavily on intuitive designs.
In other words, in terms of geometric design, nano-kirigami offers an intelligent 3D nanofabrication method beyond traditional bottom-up, top-down and self-assembly nanofabrication techniques.
Its concept can be extended to broad nanofabrication platforms and could lead to the realization of complex optical nanostructures for sensing, computation, micro-/nano- electromechanical systems or biomedical devices.
This work, entitled "Nano-kirigami with giant optical chirality," was published in Science Advances on July 6, 2018.
The study was supported by the National Science Foundation of China, the Ministry of Science and Technology of China, the Chinese Academy of Sciences, the Chinese Scholarship Council and grants from the U.S government.
LI Jiafang | EurekAlert!
Hubble watches interstellar comet Borisov speed past the sun
13.12.2019 | ESA/Hubble Information Centre
NASA Mission Delivers Best-ever Pulsar Measurements - Research Group of TU Darmstadt involved
13.12.2019 | Technische Universität Darmstadt
Vaccinia viruses serve as a vaccine against human smallpox and as the basis of new cancer therapies. Two studies now provide fascinating insights into their unusual propagation strategy at the atomic level.
For viruses to multiply, they usually need the support of the cells they infect. In many cases, only in their host’s nucleus can they find the machines,...
More than one hundred and fifty years have passed since the publication of James Clerk Maxwell's "A Dynamical Theory of the Electromagnetic Field" (1865). What would our lives be without this publication?
It is difficult to imagine, as this treatise revolutionized our fundamental understanding of electric fields, magnetic fields, and light. The twenty original...
In a joint experimental and theoretical work performed at the Heidelberg Max Planck Institute for Nuclear Physics, an international team of physicists detected for the first time an orbital crossing in the highly charged ion Pr⁹⁺. Optical spectra were recorded employing an electron beam ion trap and analysed with the aid of atomic structure calculations. A proposed nHz-wide transition has been identified and its energy was determined with high precision. Theory predicts a very high sensitivity to new physics and extremely low susceptibility to external perturbations for this “clock line” making it a unique candidate for proposed precision studies.
Laser spectroscopy of neutral atoms and singly charged ions has reached astonishing precision by merit of a chain of technological advances during the past...
The ability to investigate the dynamics of single particle at the nano-scale and femtosecond level remained an unfathomed dream for years. It was not until the dawn of the 21st century that nanotechnology and femtoscience gradually merged together and the first ultrafast microscopy of individual quantum dots (QDs) and molecules was accomplished.
Ultrafast microscopy studies entirely rely on detecting nanoparticles or single molecules with luminescence techniques, which require efficient emitters to...
Graphene, a two-dimensional structure made of carbon, is a material with excellent mechanical, electronic and optical properties. However, it did not seem suitable for magnetic applications. Together with international partners, Empa researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronic applications. The results have just been published in the renowned journal Nature Nanotechnology.
Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties – for example,...
03.12.2019 | Event News
15.11.2019 | Event News
15.11.2019 | Event News
13.12.2019 | Life Sciences
13.12.2019 | Physics and Astronomy
13.12.2019 | Life Sciences