Tunable exciton–polariton condensation in a two-dimensional Lieb lattice at room temperature

AbstractMicrocavities with embedded optically active materials allow to create exciton–polariton condensates in the strong light–matter interaction regime. These condensates exhibit quantum fluid properties up to room temperature, and, when crystal-like lattices are imprinted in the cavity, they can be used to emulate and study solid-state physics toy models. Here, we demonstrate room temperature polariton condensation in a nano-fabricated two-dimensional Lieb lattice with an organic polymer. We exploit the tunability of our open cavity to selectively condense into the s-, p- and d-lattice band manifolds. Furthermore, we interferometrically measure long-range first-order coherence across the lattice and assess the influence of the disorder in the system. These are key first steps to investigate extended topological polariton systems at ambient conditions.

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Optical switching of topological phase in a perovskite polariton lattice

Science Advances ◽

10.1126/sciadv.abf8049 ◽

2021 ◽

Vol 7 (21) ◽

pp. eabf8049

Author(s):

Rui Su ◽

Sanjib Ghosh ◽

Timothy C. H. Liew ◽

Qihua Xiong

Keyword(s):

Optical Switching ◽

Room Temperature ◽

Optical Pumping ◽

Optical Nonlinearity ◽

Edge States ◽

Ambient Conditions ◽

Strong Light ◽

Exciton Polaritons ◽

Matter Interaction ◽

Light Matter Interaction

Strong light-matter interaction enriches topological photonics by dressing light with matter, which provides the possibility to realize active nonlinear topological devices with immunity to defects. Topological exciton polaritons—half-light, half-matter quasiparticles with giant optical nonlinearity—represent a unique platform for active topological photonics. Previous demonstrations of exciton polariton topological insulators demand cryogenic temperatures, and their topological properties are usually fixed. Here, we experimentally demonstrate a room temperature exciton polariton topological insulator in a perovskite zigzag lattice. Polarization serves as a degree of freedom to switch between distinct topological phases, and the topologically nontrivial polariton edge states persist in the presence of onsite energy perturbations, showing strong immunity to disorder. We further demonstrate exciton polariton condensation into the topological edge states under optical pumping. These results provide an ideal platform for realizing active topological polaritonic devices working at ambient conditions, which can find important applications in topological lasers, optical modulation, and switching.

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Room-Temperature Strong Light–Matter Interaction with Active Control in Single Plasmonic Nanorod Coupled with Two-Dimensional Atomic Crystals

Nano Letters ◽

10.1021/acs.nanolett.7b01344 ◽

2017 ◽

Vol 17 (8) ◽

pp. 4689-4697 ◽

Cited By ~ 111

Author(s):

Jinxiu Wen ◽

Hao Wang ◽

Weiliang Wang ◽

Zexiang Deng ◽

Chao Zhuang ◽

...

Keyword(s):

Active Control ◽

Room Temperature ◽

Two Dimensional ◽

Strong Light ◽

Matter Interaction ◽

Light Matter Interaction

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Transient exciton-polariton dynamics in WSe2by ultrafast near-field imaging

Science Advances ◽

10.1126/sciadv.aat9618 ◽

2019 ◽

Vol 5 (2) ◽

pp. eaat9618 ◽

Cited By ~ 15

Author(s):

M. Mrejen ◽

L. Yadgarov ◽

A. Levanon ◽

H. Suchowski

Keyword(s):

Room Temperature ◽

Near Infrared ◽

Coherent Control ◽

Near Field ◽

Imaging Method ◽

Strong Light ◽

Pump Probe ◽

Near Field Imaging ◽

Light Matter Interaction ◽

Field Imaging

Van der Waals (vdW) materials offer an exciting platform for strong light-matter interaction enabled by their polaritonic modes and the associated deep subwavelength light confinement. Semiconductor vdW materials such as WSe2are of particular interest for photonic and quantum integrated technologies because they sustain visible–near-infrared (VIS-NIR) exciton-polariton (EP) modes at room temperature. Here, we develop a unique spatiotemporal imaging technique at the femtosecond-nanometric scale and observe the EP dynamics in WSe2waveguides. Our method, based on a novel ultrafast broadband intrapulse pump-probe near-field imaging, allows direct visualization of EP formation and propagation in WSe2showing, at room temperature, ultraslow EP with a group velocity ofvg~ 0.017c. Our imaging method paves the way for in situ ultrafast coherent control and extreme spatiotemporal imaging of condensed matter.

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Lower excitons strong light matter interaction in plasmonic tweezers

10.21203/rs.3.rs-74899/v1 ◽

2020 ◽

Author(s):

Yunfei Zou ◽

Gang Song ◽

Naien Wang ◽

Li Yu

Keyword(s):

Optical Force ◽

Ambient Conditions ◽

Strong Light ◽

Maxwell Stress Tensor ◽

Coupling System ◽

Matter Interaction ◽

Coupling Force ◽

Light Matter Interaction ◽

J Aggregates ◽

Trapping Performance

Abstract Plasmonic nanocavity has been an excellent platform to study light matter interaction under ambient conditions and within sub-diffraction volumes. However, controlled strong light matter interaction in the plasmonic system has rarely been reported. Here, we design a plasmonic tweezers, which can trap a molecular J-aggregates, and be a plasmonic cavity to investigate the strong light matter interaction. We use finite-difference time-domain methods and Maxwell stress tensor to evaluate the optical response and the trapping performance. With the help of coupled oscillator model and virtual excitons theory, we analyze the strong coupling progress in lower excitons system, we further introduce a `coupling force' parameter to characterize the relationship between the optical force and model volume in the coupling system. The proposed method offers a way to locate a molecular J-aggregates in a plasmonic tweezers for investigating optical force performance and strong light matter interaction.

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Design and Tailoring of Two-dimensional Schottky, PN and Tunnelling Junctions for Electronics and Optoelectronics

Nanoscale ◽

10.1039/d1nr00318f ◽

2021 ◽

Author(s):

Liang Lv ◽

Jun Yu ◽

Man Hu ◽

Shuming Yin ◽

Fuwei Zhuge ◽

...

Keyword(s):

Carrier Mobility ◽

2D Materials ◽

Optoelectronic Devices ◽

Two Dimensional ◽

Strong Light ◽

Matter Interaction ◽

Light Matter Interaction

Owing to their superior carrier mobility, strong light-matter interaction, and flexibility at the atomically thin thickness, two-dimensional (2D) materials are attracting wide interests in electronic and optoelectronic devices, including rectifying...

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Polymorphic gallium for active resonance tuning in photonic nanostructures: from bulk gallium to two-dimensional (2D) gallenene

Nanophotonics ◽

10.1515/nanoph-2020-0314 ◽

2020 ◽

Vol 9 (14) ◽

pp. 4233-4252

Author(s):

Yael Gutiérrez ◽

Pablo García-Fernández ◽

Javier Junquera ◽

April S. Brown ◽

Fernando Moreno ◽

...

Keyword(s):

Optical Properties ◽

Room Temperature ◽

Phase Change Materials ◽

Two Dimensional ◽

Active Materials ◽

Promising Candidate ◽

Plasmonic Structures ◽

Resonance Tuning ◽

The Many ◽

Optical Behavior

AbstractReconfigurable plasmonics is driving an extensive quest for active materials that can support a controllable modulation of their optical properties for dynamically tunable plasmonic structures. Here, polymorphic gallium (Ga) is demonstrated to be a very promising candidate for adaptive plasmonics and reconfigurable photonics applications. The Ga sp-metal is widely known as a liquid metal at room temperature. In addition to the many other compelling attributes of nanostructured Ga, including minimal oxidation and biocompatibility, its six phases have varying degrees of metallic character, providing a wide gamut of electrical conductivity and optical behavior tunability. Here, the dielectric function of the several Ga phases is introduced and correlated with their respective electronic structures. The key conditions for optimal optical modulation and switching for each Ga phase are evaluated. Additionally, we provide a comparison of Ga with other more common phase-change materials, showing better performance of Ga at optical frequencies. Furthermore, we first report, to the best of our knowledge, the optical properties of liquid Ga in the terahertz (THz) range showing its broad plasmonic tunability from ultraviolet to visible-infrared and down to the THz regime. Finally, we provide both computational and experimental evidence of extension of Ga polymorphism to bidimensional two-dimensional (2D) gallenene, paving the way to new bidimensional reconfigurable plasmonic platforms.

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Visible-light-initiated Catalyst-free Oxidative Cleavage of Triaryl-Substituted Alkenes C=C Bonds under Ambient Conditions

Green Chemistry ◽

10.1039/d1gc00716e ◽

2021 ◽

Author(s):

Wenjing Li ◽

Shun Li ◽

Lihua Luo ◽

Yichen Ge ◽

Jiaqi Xu ◽

...

Keyword(s):

Visible Light ◽

Room Temperature ◽

Ambient Air ◽

Oxidative Cleavage ◽

Ambient Conditions ◽

Blue Led ◽

Catalyst Free

The catalyst-free oxidative cleavage of (Z)-triaryl-substituted alkenes bearing pyridyl motif with ambient air under irradiation of blue LED at room temperature has been developed. The reaction was facile and scalable,...

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Foldable and washable textile-based OLEDs with a multi-functional near-room-temperature encapsulation layer for smart e-textiles

npj Flexible Electronics ◽

10.1038/s41528-021-00112-0 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

So Yeong Jeong ◽

Hye Rin Shim ◽

Yunha Na ◽

Ki Suk Kang ◽

Yongmin Jeon ◽

...

Keyword(s):

Room Temperature ◽

Wearable Electronics ◽

Ambient Conditions ◽

Light Emitting ◽

Stable Operating ◽

Mechanical Durability ◽

Potential Applications ◽

Wearable Electronic ◽

Data Signal ◽

Wearable Electronic Devices

AbstractWearable electronic devices are being developed because of their wide potential applications and user convenience. Among them, wearable organic light emitting diodes (OLEDs) play an important role in visualizing the data signal processed in wearable electronics to humans. In this study, textile-based OLEDs were fabricated and their practical utility was demonstrated. The textile-based OLEDs exhibited a stable operating lifetime under ambient conditions, enough mechanical durability to endure the deformation by the movement of humans, and washability for maintaining its optoelectronic properties even in water condition such as rain, sweat, or washing. In this study, the main technology used to realize this textile-based OLED was multi-functional near-room-temperature encapsulation. The outstanding impermeability of TiO2 film deposited at near-room-temperature was demonstrated. The internal residual stress in the encapsulation layer was controlled, and the device was capped by highly cross-linked hydrophobic polymer film, providing a highly impermeable, mechanically flexible, and waterproof encapsulation.

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