Phys.org January 16, 2023 Foam materials can adjust the reflection and absorption of microwaves, enabling a tunable electromagnetic interference shielding capability. But their thickness of several millimetres hinders their application in integrated electronics. Researchers at Drexel University have developed a method for modulating the reflection and absorption of incident electromagnetic waves using various submicrometre-thick MXene thin films. The reversible tunability of electromagnetic interference shielding effectiveness was realized by electrochemically driven ion intercalation and de-intercalation; this resulted in charge transfer efficiency with different electrolytes, accompanied by expansion and shrinkage of the MXene layer spacing. They demonstrated an irreversible electromagnetic interference shielding […]
Category Archives: Secure communication
Eavesdroppers can hack 6G frequency with DIY metasurface
Science Daily May 16, 2022 Metasurfaces enable controllable manipulation of electromagnetic waves and have been shown to improve wireless communications in many diverse ways. A team of researchers in the US (Rice University, Brown University) defined and experimentally demonstrated a “MetaSurface-in-the-Middle” (MSITM) attack. In this attack, the adversary Eve placed a metasurface in the path of a directive transmission between Alice and Bob and targeted to re-direct a portion of the signal towards herself, without being detected. They showed how to design a metasurface that induces abrupt phase changes at the interface of the metasurface to controllably diffract directional links […]
A ‘beyond-quantum’ equivalence principle for superposition and entanglement
Phys.org May 2, 2022 An international team of researchers (France, Germany, Spain) has discovered a new connection between superposition and entanglement that does not assume that quantum theory is correct. They proved that given any two general probabilistic theories (GPTs) the following are equivalent: (i) each theory is nonclassical, (ii) each theory satisfies a strong notion of incompatibility equivalent to the existence of “superpositions” and (iii) the two theories can be entangled, in the sense that their composite exhibits either entangled states or entangled measurements. Intuitively, in the post-quantum GPT setting, a superposition is a set of two binary ensembles […]