Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Density and Archimedes' Principle01:05

Density and Archimedes' Principle

6.7K
When a lump of clay is dropped into water, it sinks. But if the same lump of clay is molded into the shape of a boat, it starts to float. Because of its shape, the clay boat displaces more water than the lump and experiences a greater buoyant force, even though its mass is the same. The same holds true for steel ships. The average density of an object majorly determines if the object will float. If an object's average density is less than that of the surrounding fluid, it will float. The...
6.7K
Potential Due to a Magnetized Object01:24

Potential Due to a Magnetized Object

324
Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...
324
Potential Due to a Polarized Object01:29

Potential Due to a Polarized Object

443
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
443
Symmetry in Maxwell's Equations01:28

Symmetry in Maxwell's Equations

3.5K
Once the fields have been calculated using Maxwell's four equations, the Lorentz force equation gives the force that the fields exert on a charged particle moving with a certain velocity. The Lorentz force equation combines the force of the electric field and of the magnetic field on the moving charge. Maxwell's equations and the Lorentz force law together encompass all the laws of electricity and magnetism. The symmetry that Maxwell introduced into his mathematical framework may not be...
3.5K
Magnetic Damping01:17

Magnetic Damping

508
Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a strong magnet, significant drag acts on the bob as it enters and leaves the field, quickly damping the motion.
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
508
Differential Form of Maxwell's Equations01:17

Differential Form of Maxwell's Equations

539
James Clerk Maxwell (1831–1879) was one of the significant contributors to physics in the nineteenth century. He is probably best known for having combined existing knowledge of the laws of electricity and the laws of magnetism with his insights to form a complete overarching electromagnetic theory, represented by Maxwell's equations. The four basic laws of electricity and magnetism were discovered experimentally through the work of physicists such as Oersted, Coulomb, Gauss, and...
539

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Foot-and-Mouth Disease Virus Persistence Divergence Within Serotypes and Vaccine Doses in Vaccinated Cattle.

Transboundary and emerging diseases·2026
Same author

Insights into Cryoprotective Mechanisms of Food-Derived Antifreeze Peptides: Coordinated Regulation of Intra- and Extra-Cellular Protection.

Journal of agricultural and food chemistry·2026
Same author

Integrated microfluidic biosensors: shaping the future of quantitative life sciences and on-chip molecular diagnostics.

Lab on a chip·2026
Same author

Defect engineering boosts CC bond cleavage for highly efficient ethylene glycol electrooxidation on Pd<sub>2</sub>Pb<sub>3</sub>Zn<sub>4</sub> intermetallic compound.

Journal of colloid and interface science·2026
Same author

New Insights into the Mechanisms of Bitterness and Astringency in Chitosan Oligosaccharide Complexes.

Journal of agricultural and food chemistry·2026
Same author

Development and validation of a predictive model for short-term symptom relief after organophosphate poisoning.

Frontiers in medicine·2026
Same journal

The TaMYB55-TaSnRK1α1-TabZIP9 module confers heat stress tolerance in wheat.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same journal

Superstatistics approach to turbulent circulation fluctuations.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same journal

A molecular timescale for evolution of cobamide biosynthesis.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same journal

Pierre Chambon, a pioneer of molecular biology and gene regulation in eukaryotes.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same journal

Granulosa cell glycogen fuels the avascular corpus luteum.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same journal

Synthetic essentiality of TRAIL/TNFSF10 in VHL-deficient renal cell carcinoma.

Proceedings of the National Academy of Sciences of the United States of America·2026
See all related articles

Related Experiment Video

Updated: Jul 30, 2025

Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
09:39

Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing

Published on: June 28, 2024

987

Active metamaterials for realizing odd mass density.

Qian Wu1, Xianchen Xu1, Honghua Qian1

  • 1Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO 65211.

Proceedings of the National Academy of Sciences of the United States of America
|May 18, 2023
PubMed
Summary
This summary is machine-generated.

Researchers developed active metamaterials with an odd mass density, enabling novel wave propagation and non-Hermitian phenomena. This innovation opens new avenues for mechanical non-Hermitian systems and advanced wave steering devices.

Keywords:
elastic metamaterialenergy phase transitionnon-Hermitian mechanical systemnon-Hermitian skin effectodd mass density

More Related Videos

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
13:44

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers

Published on: December 27, 2012

15.4K
Fabricating Metamaterials Using the Fiber Drawing Method
11:57

Fabricating Metamaterials Using the Fiber Drawing Method

Published on: October 18, 2012

13.9K

Related Experiment Videos

Last Updated: Jul 30, 2025

Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
09:39

Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing

Published on: June 28, 2024

987
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
13:44

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers

Published on: December 27, 2012

15.4K
Fabricating Metamaterials Using the Fiber Drawing Method
11:57

Fabricating Metamaterials Using the Fiber Drawing Method

Published on: October 18, 2012

13.9K

Area of Science:

  • Physics
  • Materials Science
  • Metamaterials

Background:

  • Active solids exhibit unusual elastic stiffness tensors leading to non-Hermitian phenomena.
  • Non-Hermitian physics in mechanical systems is an emerging field with potential applications.

Purpose of the Study:

  • To introduce and experimentally validate active metamaterials with an odd mass density tensor.
  • To explore the unique wave propagation phenomena arising from odd mass density in active solids.
  • To investigate the potential for novel mechanical non-Hermitian systems and wave steering devices.

Main Methods:

  • Designing metamaterials with inner resonators and asymmetric feed-forward control.
  • Utilizing active and nonconservative forces to create unbalanced mass density coupling.
  • Experimentally validating odd mass through one-dimensional nonsymmetric wave coupling.
  • Numerically simulating and experimentally demonstrating two-dimensional wave propagation.

Main Results:

  • Demonstrated active metamaterials with an odd mass density tensor.
  • Observed energy-unbroken and energy-broken phases separated by exceptional points.
  • Revealed wave anisotropy and directional energy gain due to odd mass.
  • Confirmed the existence of the non-Hermitian skin effect with localized boundary modes.

Conclusions:

  • The concept of odd mass density provides a new platform for mechanical non-Hermitian systems.
  • Active metamaterials with odd mass enable control over wave propagation and energy.
  • This research paves the way for next-generation wave steering devices.