As complementary metal-oxide-semiconductor (CMOS) approaches atomic level, a molecular-size shape-changing memory technology is maturing, reversibly changing the lattice structure of molybdenum telluride (MoTe2).
According to Zhang Xiang, a professor at UC Berkeley and director of materials science at Lawrence Berkeley National Laboratory (LBNL), this approach requires only a few atoms to take 0 and 1 as Shape memory, in order to achieve a solid state memory capable of storing mechanical materials, and can be used with the future atomic level processor.
The technique uses electron injection - instead of encoding the memory in terms of charges, spins, or any brief amount, it is possible to change the lattice structure of MoTe2 reversibly.According to Zhang Xiang, rearrangement of atoms through electrical stimulation Structure that changes the properties of the material so that less energy than that required to transfer chemistry can be used to form and sense 0 and 1 or thermally induce transitions as in phase-change memory.
The key to this process is the use of transition metal dichalcogenides (TMDs) - in this case MoTe2's atomic monolayer allows its internal lattice structure to be transported through the structure by electron transfer between two steady states To be changed.Zhang Xiang jointly UC Berkeley and Berkeley National Laboratory researchers jointly study, in their MoTe2 film example, the two stable lattice structure is a symmetrical 2H arrangement, as opposed to 1T structure .
Berkeley researchers are currently trying to use a variety of TMDs as the target material for the electron injection of their deformed lattice structure, but MoTe2 is favored for its changing electronic and photonic properties. The researchers' goal is to create a library of 'designer films' that can be used in computer and optical applications, including solar panels.
In 2D, single-layer TMD films, electrical and optical properties can be electronically altered, including resistance, spin transport, and phase-related shape changes used by Berkeley's research methods.
Zhang Xiang said the researchers verify the concept of the use of 'electrostatic doping' electrons (rather than atoms), used as a dopant.After the ionic liquid coating MoTe2 monolayer, the researchers use the injection of electron doping Agent to alter the shape of the lattice and is said to create a defect-free material The resulting 1T structure is tilted and metallic, making it easy to segregate from the 2H atomic lattice arrangement of semimetallic structures The original 2H structure was restored by applying a lower voltage to remove the doping electrons.
The DoE sponsors the research program DoE's Office of Essential Energy Sciences performs transmission research and its Light Conversion Materials (LMIs) at the Energy Conversion Frontier Research Center (EFRC) ) DOE EFRC and the National Science Foundation (NSF) support the project through device design and manufacturing, and Tsinghua University in China provides a resource for research at Stanford University Staff also contributed, as well as grants from the Army Research Office, Naval Research Office, NSF and Stanford University Graduate Scholarships.
Compile: Susan Hong