Scientists create a new form of light matter in a quasicrystal

Researchers have for the first time created a reconfigurable polariton 2D quasicrystal. The team from the Skolkovo Institute of Science and Technology (Skoltech), in collaboration with colleagues from the University of Iceland, the University of Warsaw, and the Institute of Spectroscopy of the Russian Academy of Sciences, demonstrated that this unique state of matter exhibits long-range order and a novel type of phase synchronization, opening new pathways for research into exotic phenomena such as supersolids and superfluidity in aperiodic settings. The breakthrough, published in Science Advances, was achieved using exciton-polaritons—hybrid quasiparticles that are part light and part matter. By arranging these polaritons in a Penrose tiling, a famous aperiodic pattern with five-fold symmetry, the team observed the emergence of a macroscopic coherent state where the individual nodes synchronized in a nontrivial way, unlike anything seen in conventional periodic crystals.

aaaaaaaaaaaaAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHOHMYGOD

Holy crap! Fuck! What the fuck!

This group made a Bose-Einstein condensate superfluid at room temperature! AT ROOM TEMPERATURE! AAAAAHHHHHHHHHHHHHHHHHHH!!!!!!!

This is so fucking important! It means superfluid and BEC experiments can be done at room temperature with just some ugly-ass organic molecules, a good cavity, and a femtosecond laser! 

I love this! I love this so much! 

Also polaritons are so weird. They are the binding of light to the abstract ‘not really a force but it happens like this anyway’ energetic manifestation of the N-2 eigenvalue crossing principle for N-dimension Hamiltonians as applied to 2-degrees-of-freedom dipole excitations in band-gapped systems which can’t dump that excess energy. Which, no, is not a sensible statement and you should not be expected to understand it. I study quantum optics for a living, spend way more time reading up on this stuff than most of my colleagues do (because it interests me) and it still took me way, way too fucking long to parse that and understand what the fuck it meant when I first started reading up on polaritons. 

But this research group took polaritons and did even weirder than normal stuff to them that I still don’t understand yet (despite having read the paper twice now) and fucking made them into a BEC superfluid. At room temperature.

For the first time, physicists have achieved 'liquid light' at room temperature, making this strange form of matter more accessible than ever.

This matter is both a superfluid, which has zero friction and viscosity, and a kind of Bose-Einstein condensate - sometimes described as the fifth state of matter - and it allows light to actually flow around objects and corners.

Regular light behaves like a wave, and sometimes like a particle, always travelling in a straight line. That's why your eyes can't see around corners or objects. But under extreme conditions, light can also act like a liquid, and actually flow around objects.

Bose-Einstein condensates are interesting to physicists because in this state, the rules switch from classical to quantum physics, and matter starts to take on more wave-like properties.

They are formed at temperatures close to absolute zero and exist for only fractions of a second.

But in this study, researchers report making a Bose-Einstein condensate at room temperature by using a Frankenstein mash-up of light and matter.

"The extraordinary observation in our work is that we have demonstrated that superfluidity can also occur at room-temperature, under ambient conditions, using light-matter particles called polaritons," says lead researcher Daniele Sanvitto, from the CNR NANOTEC Institute of Nanotechnology in Italy.

New light behavior discovered in gypsum

A new study published in Science Advances by researchers from the National Graphene Institute at University of Manchester and the University of Oviedo, has revealed a previously unseen behavior of light in gypsum, a mineral better known for its use in building plaster and chalk. The team uncovered a rare type of wave, known as a shear phonon polariton, in a two-dimensional form of the material. Phonon polaritons are light-matter hybrid waves that emerge when light interacts with atomic vibrations in certain crystals. They can travel through materials in unusual ways and concentrate light into extremely small volumes. In this study, the researchers found that in thin films of gypsum, these waves undergo a topological transition, shifting from hyperbolic to elliptical behavior, passing through a unique canalized state.

A research team consisting of Professor Kyoung-Duck Park and Hyeongwoo Lee, an integrated PhD student, from the Department of Physics at Pohang University of Science and Technology (POSTECH) has pioneered an innovative technique in ultra-high-resolution spectroscopy. Their breakthrough marks the world's first instance of electrically controlling polaritons -- hybridized light-matter particles -- at room temperature. Polaritons are "half-light half-matter" hybrid particles, having both the characteristics of photons -- particles of light -- and those of solid matter. Their unique characteristics exhibit properties distinct from both traditional photons and solid matter, unlocking the potential for next-generation materials, particularly in surpassing performance limitations of optical displays. Until now, the inability to electrically control polaritons at room temperature on a single particle level has hindered their commercial viability.

Researchers find a way to reduce the overheating of semiconductor devices

The demand to shrink the size of semiconductors coupled with the problem of the heat generated at the hot spots of the devices not being effectively dispersed has negatively affected the reliability and durability of modern devices. Existing thermal management technologies have not been up to the task. Thus, the discovery of a new way of dispersing heat by using surface waves generated on the thin metal films over the substrate is an important breakthrough.

KAIST announced that Professor Bong Jae Lee's research team in the Department of Mechanical Engineering succeeded in measuring a newly observed transference of heat induced by "surface plasmon polariton" in a thin metal film deposited on a substrate for the first time in the world.

Surface plasmon polariton (SPP) refers to a surface wave formed on the surface of a metal as a result of strong interaction between the electromagnetic field at the interface between the dielectric and the metal and the free electrons on the metal surface and similar collectively vibrating particles.

Ancient Namibian Gemstone Holds Key to Future Quantum Computers

A special form of light made using an ancient Namibian gemstone could be the key to new light-based quantum computers, which could solve long-held scientific mysteries, according to new research led by the University of St Andrews.

The research, conducted in collaboration with scientists at Harvard University in the US, Macquarie University in Australia, and Aarhus University in Denmark and published in Nature Materials, used a naturally mined cuprous oxide (Cu2O) gemstone from Namibia to produce Rydberg polaritons, the largest hybrid particles of light and matter ever created.

Rydberg polaritons switch continually from light to matter and back again. In Rydberg polaritons, light and matter are like two sides of a coin, and the matter side is what makes polaritons interact with each other.

Revealing new states in 2D materials

Atomically thin two-dimensional (2D) materials can provide highly interesting excitonic properties, which render them an attractive platform to explore polaritonic physics. 

In the literature, a variety of inorganic exciton-polariton systems have been studied experimentally and described theoretically using the broadly accepted model of two coupled oscillators, where only the coupling between excitons and cavity photons is considered.

Now, Donghai Li and a group of researchers from Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany, have found that placing 2D semiconductors in microcavities can lead to a strong interaction between not just excitons and cavity photons but also with phonons. The team believes that their results could shift the paradigm of exciton-polariton physics in 2D materials by highlighting and quantifying the role of phonons therein.