Science Daily August 16, 2023 Recent studies were able to modify some of the most defining features of light utilizing the strong coupling of light and matter in optical cavities. An international team of researchers (City College of New York, City University of New York, University of Washington, University of Michigan, MIT, Spain) studied the magneto-optical properties of a van der Waals magnet that supports strong coupling of photons and excitons even in the absence of external cavity mirrors. In the layered magnetic semiconductor CrSBr polaritons were shown to substantially increase the spectral bandwidth of correlations between the magnetic, electronic, […]
Tag Archives: Polaritons
New breakthrough shows how short pulses of light destroy particles
Phys.org July 6, 2023 Molecular polaritons are hybrid light-matter states that emerge when a molecular transition strongly interacts with photons in a resonator. At optical frequencies, this interaction unlocks a way to explore and control new chemical phenomena at the nanoscale. However achieving such control at ultrafast timescales is challenging as it requires a deep understanding of the dynamics of the collectively coupled molecular excitation and the light modes. An international team of researchers (Germany, Italy, Sweden, Spain, Luxembourg) investigated the dynamics of collective polariton states, realized by coupling molecular photoswitches to optically anisotropic plasmonic nanoantennas. Pump-probe experiments revealed an […]
Proposed perovskite-based device combines aspects of electronics and photonics
Phys.org May 12, 2023 Hybrid perovskites have emerged as a promising material candidate for exciton-polariton (polariton) optoelectronics. Many applications demand precise control of polariton interactions. Thus far, the primary mechanisms by which polaritons relax in perovskites remain unclear. An international team of researchers (USA – MIT, Spain, Italy) sandwiched perovskite in between two precisely spaced reflective surfaces and stimulated them with laser beams. Then they were able to directly control the momentum of exciton-polariton pairs. The combined sate could be perturbed either with light or charge in a more energy-efficient manner. Halide perovskites harvest light well, and turn photons into […]
Atomically-smooth gold crystals help to compress light for nanophotonic applications
Phys.org July 13, 2022 An international team of researchers (South Korea, Denmark, Switzerland, Japan, USA – University of Minnesota) used a highly sensitive scanning near-field optical microscope (SNOM) to directly measure the optical fields of the hyperbolic image phonon-polaritons (HIP) propagating in a 63 nm-thick slab of hexagonal boron nitride (h-BN) on a monocrystalline gold substrate, showing the mid-infrared light waves in dielectric crystal compressed by a hundred times. They showed that the phonon-polaritons in van der Waals crystals can be significantly more compressed without sacrificing their lifetime. Practically zero surface scattering and extremely small ohmic loss in gold at […]
More efficient optical quantum gates
Phys.org May 13, 2022 Progress in optical quantum information processing is hampered by the low efficiency of the two-qubit quantum gates realized so far. Researchers in Germany demonstrated an optical two-qubit gate with an average efficiency above 40%, thus outperforming the previous record by a factor of almost 4. They accomplished this with electromagnetically induced transparency. Incoming photons are converted into polaritons in highly excited Rydberg state. Any two atoms in such a state have a strong interaction, even at large separations. When two photons enter the resonator, both become polaritons and their Rydberg components interact. When the excitations leave […]
Discovery of matter-wave polaritons sheds new light on photonic quantum technologies
Phys.org April 6, 2022 Exploiting the interaction between polaritons has led to the realization of superfluids of light as well as of strongly correlated phases in the microwave domain, with similar efforts underway for microcavity excitons–polaritons. Researchers at Stony Brook University have developed an ultracold-atom analogue of an exciton–polariton system in which interacting polaritonic phases can be studied with full tunability and in the absence of dissipation. In their optical lattice system, they replaced exciton by an atomic excitation, whereas an atomic matter wave was substituted for the photon under a strong dynamical coupling between the two constituents that hybridizes […]
Intriguing particles emerge when two photons couple
EurekAlert March 2, 2021 An international team of researchers (UK, Russia) has reported a way to create quasiparticles that bind together two differently coloured particles of light. They have named these formations photon-photon polaritons. They tuned a laser to the specific resonance frequency where a photon is expected to be absorbed, yet no resonance absorption happened. Instead, the photon-photon interaction made up two new resonance frequencies away from the old one. The microresonator provided a whole set of split resonances, where each photon-photon pair displayed its own momentum and energy, allowing the researchers to apply the quasiparticle concept and calculate […]
Scientists combine light and matter to make particles with new behaviors
Phys.org July 4, 2019 Researchers at University of Chicago developed techniques to manipulate quantum matter using Floquet engineering. By varying the intensity of a laser field tuned precisely to an atomic resonance, the team was able to shift the orbitals of an electron. Shaking the orbitals by periodically varying this intensity produced the desired copies. By allowing photons to interact with these shaken atoms, the team has created what they call “Floquet polaritons”—quasi-particles which are part-light and part-atom, and unlike regular photons, interact with each other quite strongly. These interactions are essential for making matter from light. Making polaritons with […]
Scientists develop polariton nano-laser operating at room temperature
Phys.org May 20, 2019 Progress toward room temperature polariton nanolasers has been limited by the thermal instability of excitons and the inherently low-quality factors of nanocavities. An international team of researchers (South Korea, University of Pennsylvania) has produced a quantum well on the sidewall of a nanostructure semiconductor and succeeded in maintaining thermally stable excitons even at room temperature. The quantum well structure contributed to the formation of more efficient and stable exciton-polariton states than before by strengthening the coupling of exciton and light inside the nanostructure semiconductor. Their polariton nano-lasers are stable at room temperature and operate at only […]