scholarly journals Dirac-like cone-based electromagnetic zero-index metamaterials

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Yang Li ◽  
C. T. Chan ◽  
Eric Mazur
Keyword(s):  
Large Area ◽  
Fundamental Physics ◽  
Electromagnetic Mode ◽  
Potential Applications ◽  
Refractive Index Material ◽  
Efficient Coupling ◽  
On Chip ◽  
Nonlinear Signal ◽  
Collective Emission ◽  
Zero Index

AbstractMetamaterials with a Dirac-like cone dispersion at the center of the Brillouin zone behave like an isotropic and impedance-matched zero refractive index material at the Dirac-point frequency. Such metamaterials can be realized in the form of either bulk metamaterials with efficient coupling to free-space light or on-chip metamaterials that are efficiently coupled to integrated photonic circuits. These materials enable the interactions of a spatially uniform electromagnetic mode with matter over a large area in arbitrary shapes. This unique optical property paves the way for many applications, including arbitrarily shaped high-transmission waveguides, nonlinear enhancement, and phase mismatch-free nonlinear signal generation, and collective emission of many emitters. This review summarizes the Dirac-like cone-based zero-index metamaterials’ fundamental physics, design, experimental realizations, and potential applications.

scholarly journals Ultra-low-loss on-chip zero-index materials

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Tian Dong ◽  
Jiujiu Liang ◽  
Sarah Camayd-Muñoz ◽  
Yueyang Liu ◽  
Haoning Tang ◽  
...  
Keyword(s):  
Spatial Coherence ◽  
Single Mode ◽  
Nonlinear Propagation ◽  
Small Scale ◽  
Destructive Interference ◽  
Dirac Cone ◽  
Large Area ◽  
Low Loss ◽  
On Chip ◽  
Zero Index

AbstractLight travels in a zero-index medium without accumulating a spatial phase, resulting in perfect spatial coherence. Such coherence brings several potential applications, including arbitrarily shaped waveguides, phase-mismatch-free nonlinear propagation, large-area single-mode lasers, and extended superradiance. A promising platform to achieve these applications is an integrated Dirac-cone material that features an impedance-matched zero index. Although an integrated Dirac-cone material eliminates ohmic losses via its purely dielectric structure, it still entails out-of-plane radiation loss, limiting its applications to a small scale. We design an ultra-low-loss integrated Dirac cone material by achieving destructive interference above and below the material. The material consists of a square array of low-aspect-ratio silicon pillars embedded in silicon dioxide, featuring easy fabrication using a standard planar process. This design paves the way for leveraging the perfect spatial coherence of large-area zero-index materials in linear, nonlinear, and quantum optics.

Microcavities

2017 ◽  
Author(s):  
Alexey V. Kavokin ◽  
Jeremy J. Baumberg ◽  
Guillaume Malpuech ◽  
Fabrice P. Laussy
Keyword(s):  
Quantum Wells ◽  
Strong Light ◽  
Fundamental Physics ◽  
Postgraduate Students ◽  
Optical Cavities ◽  
Semiconductor Quantum Wells ◽  
Exciton Polaritons ◽  
Different Types ◽  
Potential Applications ◽  
Experimental Findings

Both rich fundamental physics of microcavities and their intriguing potential applications are addressed in this book, oriented to undergraduate and postgraduate students as well as to physicists and engineers. We describe the essential steps of development of the physics of microcavities in their chronological order. We show how different types of structures combining optical and electronic confinement have come into play and were used to realize first weak and later strong light–matter coupling regimes. We discuss photonic crystals, microspheres, pillars and other types of artificial optical cavities with embedded semiconductor quantum wells, wires and dots. We present the most striking experimental findings of the recent two decades in the optics of semiconductor quantum structures. We address the fundamental physics and applications of superposition light-matter quasiparticles: exciton-polaritons and describe the most essential phenomena of modern Polaritonics: Physics of the Liquid Light. The book is intended as a working manual for advanced or graduate students and new researchers in the field.

Precise Cache Profiling for Studying Radiation Effects

2021 ◽  
Vol 20 (3) ◽  
pp. 1-25
Author(s):  
James Marshall ◽  
Robert Gifford ◽  
Gedare Bloom ◽  
Gabriel Parmer ◽  
Rahul Simha
Keyword(s):  
Radiation Effects ◽  
Fault Injection ◽  
Error Correcting Codes ◽  
Direct Access ◽  
Transient Faults ◽  
Large Area ◽  
Common Multiple ◽  
Single Event Upsets ◽  
On Chip ◽  
Future Work

Increased access to space has led to an increase in the usage of commodity processors in radiation environments. These processors are vulnerable to transient faults such as single event upsets that may cause bit-flips in processor components. Caches in particular are vulnerable due to their relatively large area, yet are often omitted from fault injection testing because many processors do not provide direct access to cache contents and they are often not fully modeled by simulators. The performance benefits of caches make disabling them undesirable, and the presence of error correcting codes is insufficient to correct for increasingly common multiple bit upsets. This work explores building a program’s cache profile by collecting cache usage information at an instruction granularity via commonly available on-chip debugging interfaces. The profile provides a tighter bound than cache utilization for cache vulnerability estimates (50% for several benchmarks). This can be applied to reduce the number of fault injections required to characterize behavior by at least two-thirds for the benchmarks we examine. The profile enables future work in hardware fault injection for caches that avoids the biases of existing techniques.

Structure and Electrical Properties of an Assembly of Au Nanoclusters

2001 ◽  
Vol 635 ◽  
Author(s):  
G. Muralidharan ◽  
L. Maya ◽  
T. Thundat
Keyword(s):  
Threshold Voltage ◽  
Specific Reference ◽  
Low Molecular Weight ◽  
Electrical Measurements ◽  
Monolayer Films ◽  
Au Nanoclusters ◽  
Fundamental Physics ◽  
Au Clusters ◽  
Significant Interest ◽  
Potential Applications

AbstractConduction through an assembly of nanosized clusters coupled by tunneling barriers is of significant interest both for understanding the fundamental physics involved and for potential applications. In this study, we describe a technique for preparing relatively large (dimensions of a few 100 µm to a few mm in size) monolayer films consisting of 3 nm diameter Au clusters coated with mercaptododecanoic acid, using low molecular weight-polymers as coupling agents. Electrical measurements of the assembly show non-linear characteristics. Below a certain threshold voltage, the current does not vary with an increase in voltage. Above this threshold voltage, current increases with voltage and can be described by a power-law relationship with an exponent close to unity. These characteristics of the I-V curve are discussed with specific reference to theoretical studies on conduction through an array of capacitance-coupled metallic islands and previous experimental results in similar systems.

scholarly journals Synchrony and pattern formation of coupled genetic oscillators on a chip of artificial cells

2017 ◽  
Vol 114 (44) ◽  
pp. 11609-11614 ◽  
Author(s):  
Alexandra M. Tayar ◽  
Eyal Karzbrun ◽  
Vincent Noireaux ◽  
Roy H. Bar-Ziv
Keyword(s):  
Pattern Formation ◽  
Large Scale ◽  
Reaction Diffusion ◽  
Biochemical Networks ◽  
Artificial Cells ◽  
Diffusion Dynamics ◽  
Oscillatory Reactions ◽  
Potential Applications ◽  
On Chip ◽  
Genetic Oscillators

Understanding how biochemical networks lead to large-scale nonequilibrium self-organization and pattern formation in life is a major challenge, with important implications for the design of programmable synthetic systems. Here, we assembled cell-free genetic oscillators in a spatially distributed system of on-chip DNA compartments as artificial cells, and measured reaction–diffusion dynamics at the single-cell level up to the multicell scale. Using a cell-free gene network we programmed molecular interactions that control the frequency of oscillations, population variability, and dynamical stability. We observed frequency entrainment, synchronized oscillatory reactions and pattern formation in space, as manifestation of collective behavior. The transition to synchrony occurs as the local coupling between compartments strengthens. Spatiotemporal oscillations are induced either by a concentration gradient of a diffusible signal, or by spontaneous symmetry breaking close to a transition from oscillatory to nonoscillatory dynamics. This work offers design principles for programmable biochemical reactions with potential applications to autonomous sensing, distributed computing, and biomedical diagnostics.

Efficient coupling of thermal electron Bernstein waves to the ordinary electromagnetic mode on the National Spherical Torus Experiment

2005 ◽  
Vol 12 (5) ◽  
pp. 052511 ◽  
Author(s):  
G. Taylor ◽  
P. C. Efthimion ◽  
B. P. LeBlanc ◽  
M. D. Carter ◽  
J. B. Caughman ◽  
...  
Keyword(s):  
Spherical Torus ◽  
Thermal Electron ◽  
Electromagnetic Mode ◽  
Bernstein Waves ◽  
Efficient Coupling

scholarly journals Design of an On-Chip Plasmonic Modulator Based on Hybrid Orthogonal Junctions Using Vanadium Dioxide

Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2507
Author(s):  
Gregory Beti Tanyi ◽  
Miao Sun ◽  
Christina Lim ◽  
Ranjith Rajasekharan Unnithan
Keyword(s):  
Vanadium Dioxide ◽  
Modulation Depth ◽  
Large Change ◽  
Silicon On Insulator ◽  
Nanometer Scale ◽  
High Modulation ◽  
Orthogonal Geometry ◽  
Potential Applications ◽  
On Chip ◽  
Insertion Losses

We present the design of a plasmonic modulator based on hybrid orthogonal silver junctions using vanadium dioxide as the modulating material on a silicon-on-insulator. The modulator has an ultra-compact footprint of 1.8 μm × 1 μm with a 100 nm × 100 nm modulating section based on the hybrid orthogonal geometry. The modulator takes advantage of the large change in the refractive index of vanadium dioxide during its phase transition to achieve a high modulation depth of 46.89 dB/μm. The simulated device has potential applications in the development of next generation high frequency photonic modulators for optical communications which require nanometer scale footprints, large modulation depth and small insertion losses.

scholarly journals Preparation of alginate hydrogel microparticles by gelation introducing cross-linkers using droplet-based microfluidics: a review of methods

2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Cheng Zhang ◽  
Romain Grossier ◽  
Nadine Candoni ◽  
Stéphane Veesler
Keyword(s):  
Mechanical Properties ◽  
Physicochemical Properties ◽  
Ease Of Use ◽  
Narrow Size Distribution ◽  
Future Perspectives ◽  
Alginate Hydrogel ◽  
Hydrogel Microparticles ◽  
Potential Applications ◽  
Excellent Control ◽  
On Chip

AbstractThis review examines the preparation of alginate hydrogel microparticles by using droplet-based microfluidics, a technique widely employed for its ease of use and excellent control of physicochemical properties, with narrow size distribution. The gelation of alginate is realized “on-chip” and/or “off-chip”, depending on where cross-linkers are introduced. Various strategies are described and compared. Microparticle properties such as size, shape, concentration, stability and mechanical properties are discussed. Finally, we consider future perspectives for the preparation of hydrogel microparticles and their potential applications.

Reducing Design Margins by Adaptive Compensation for Thermal and Aging Variations

2012 ◽  
pp. 201-230
Author(s):  
Zhenyu Qi ◽  
Yan Zhang ◽  
Mircea Stan
Keyword(s):  
Design Parameters ◽  
Worst Case Analysis ◽  
Transimpedance Amplifier ◽  
Large Area ◽  
Negative Bias Temperature Instability ◽  
Worst Case ◽  
Adaptive Computation ◽  
Bias Temperature Instability ◽  
Computation Efficiency ◽  
On Chip

Corner-based design and verification are based on worst-case analysis, thus introducing over-pessimism and large area and power overhead and leading to unnecessary energy consumption. Typical case-based design and verification maximize energy efficiency through design margins reduction and adaptive computation, thus helping achieve sustainable computing. Dynamically adapting to manufacturing, environmental, and usage variations is the key to shaving unnecessary design margins, which requires on-chip modules that can sense and configure design parameters both globally and locally to maximize computation efficiency, and maintain this efficiency over the lifetime of the system. This chapter presents an adaptive threshold compensation scheme using a transimpedance amplifier and adaptive body biasing to overcome the effects of temperature variation, reliability degradation, and process variation. The effectiveness and versatility of the scheme are demonstrated with two example applications, one as a temperature aware design to maintain IONto IOFFcurrent ratio, the other as a reliability sensor for NBTI (Negative Bias Temperature Instability).

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