Professor Namkyu Park, SNU·HKUST develops “virtual metal material” that can reconfigure characteristics of sound waves

2020-01-30l Hit 90


published in Nature Communications…”to design acoustic stealth technology”

The international joint research team developed a ‘digital metamaterial’ that can overcome the physical limitations of normal ‘metamaterials’. A metamaterial is a material that is artificially engineered to have a property that cannot be found in nature. A well-known application of metamaterials is the ‘invisible cloak’.

The research team of professor Namkyu Park in the Department of Electrical and Computer Engineering of SNU in cooperation with researchers from HKUST developed a metamaterial as a program rather than a structure. The results of this research were published in the online version of the international journal, ‘Nature Communications.’

The team designed a program that allows the reconfiguration of wave properties and characteristics of the frequency dispersion through mimicking the polarization of a material using digital circuits and signal processing. When the electrical charge of molecules in a dielectric material is reorganized and gains an electric dipole moment, it is polarized.

Synthesizing the physical structures was the conventional approach in generating metamaterials. In this research, however, a digital program replaced the process of synthesizing an actual material. The researchers named this digital program as ‘virtualized acoustic metamaterial’ since it does not actually exist.

Through this program, the properties of the acoustic wave can be reconfigured as intended. It can be applied to making sounds inaudible to be undetectable or soundproof or sound-absorbent architectures.

Professor Namkyu Park said, “the virtualized metamaterial technology can be used in fields where metamaterials are utilized. Our goal is to experimentally design acoustic stealth technology.”

-A schematic of a virtualized metamaterial-

The microprocessor generates a scattered wave(S) by applying the convolution operator on the incident wave(M) and the pre-designed physical properties (Y).

 

Source: http://ee.snu.ac.kr/community/news?bm=v&bbsidx=49702
Translated by Kyungjin Lee, English Editor of Department of Electrical and Computer Engineering, jin11542@snu.ac.kr