NANOSILICON FOR PHOTONIC APPLICATIONS

This presentation is a short review of some scientific insights on the possibilities of photonic applications of nanostructured silicon ( NS – Si ), porous Si ( p - Si ) and Si nanocrystals ( NC – Si ), one of the most interesting problems in nano-crystallite physics. The emission mechanism of a very bright photo-luminescence (PL) band and relatively weak electro-luminescence (EL) are presently the main issue. The basic question lies in whether the emission is an extrinsic or intrinsic property of nanocrystals. It is important from a fundamental physics viewpoint because of the potential application of Si wires and quantum dots in optoelectronic devices and information technology. Nanostructuring silicon is an effective way to turn silicon into a photonic material. It is observed that low-dimensional (one and two dimensions) silicon shows light amplification, photon confinement, photon trapping as well as non-linear optical effects. There is strong evidence of light localization and gas sensing properties of such nanostructures. Future nano-technology would replace electrical with optical interconnects, which has appealing potential for higher-speed performance and immunity to signal cross talk.

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Photonic applications of Silicon nanostructures

Material Science Research India ◽

10.13005/msri/070207 ◽

2010 ◽

Vol 7 (2) ◽

pp. 381-388

Author(s):

S. K. Ghoshal ◽

H. S. Tewari

Keyword(s):

Gas Sensing ◽

Photonic Band Gap ◽

Photo Luminescence ◽

Research Field ◽

Two Dimensions ◽

Silicon Nanostructures ◽

Nano Technology ◽

Light Amplification ◽

Photon Confinement ◽

Low Dimensional

This presentation highlights of some scientific insights on the possibilities of photonic applications of silicon nanostructures (NSs) one of the most fertile research field in nano-crystallite physics that has innumerable possibilities of device applications. Nanostructured silicon is generic name used for porous Si (p-Si) as well as Si nanocrystals (NC-Si) having length scale of the order of few nanometer. The emission of a very bright photo-luminescence (PL) band and relatively weak electro-luminescence (EL) from low-dimensional silicon has opened up new avenue in recent years. It is important from a fundamental physics viewpoint because of the potential application of Si wires and dots in opto-electronics devices and information technology. Nanostructuring silicon is an effective way to turn silicon into a photonic material. It is observed that low-dimensional (one and two dimensions) silicon shows light amplification, photon confinement, photon trapping as well as non-linear optical effects. There is strong evidence of light localization and gas sensing properties of such NSs. Future nano-technology would replace electrical with optical interconnects that has appealing potentialities for higher-speed performance and immunity to signal cross talk. A varieties of applications includes LD, LED, solar cells, sensors, photonic band gap devices and Fibonacci quasi-crystals, to cite a few.

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Transforming Pt-SnO2 Nanoparticles into Pt-SnO2 Composite Nanoceramics for Room-Temperature Hydrogen-Sensing Applications

Materials ◽

10.3390/ma14092123 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2123

Author(s):

Ming Liu ◽

Caochuang Wang ◽

Pengcheng Li ◽

Liang Cheng ◽

Yongming Hu ◽

...

Keyword(s):

Room Temperature ◽

Gas Sensing ◽

Sintering Temperature ◽

Sno2 Nanoparticles ◽

Hydrogen Sensing ◽

Sensing Applications ◽

Nanostructured Metal Oxides ◽

Low Dimensional ◽

Sensing Characteristics ◽

Nanostructured Metal

Many low-dimensional nanostructured metal oxides (MOXs) with impressive room-temperature gas-sensing characteristics have been synthesized, yet transforming them into relatively robust bulk materials has been quite neglected. Pt-decorated SnO2 nanoparticles with 0.25–2.5 wt% Pt were prepared, and highly attractive room-temperature hydrogen-sensing characteristics were observed for them all through pressing them into pellets. Some pressed pellets were further sintered over a wide temperature range of 600–1200 °C. Though the room-temperature hydrogen-sensing characteristics were greatly degraded in many samples after sintering, those samples with 0.25 wt% Pt and sintered at 800 °C exhibited impressive room-temperature hydrogen-sensing characteristics comparable to those of their counterparts of as-pressed pellets. The variation of room-temperature hydrogen-sensing characteristics among the samples was explained by the facts that the connectivity between SnO2 grains increases with increasing sintering temperature, and Pt promotes oxidation of SnO2 at high temperatures. These results clearly demonstrate that some low-dimensional MOX nanocrystals can be successfully transformed into bulk MOXs with improved robustness and comparable room-temperature gas-sensing characteristics.

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Na2Ti7O15 Nanowires with an Oriented Tunnel Structure and High Mechanical Stability: A Potential Anode of Sodium-Ion Batteries and Gas Sensing Materials

Applied Sciences ◽

10.3390/app9081673 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1673 ◽

Cited By ~ 3

Author(s):

Li-Ying Liu ◽

Yang Ding ◽

Bo Zhou ◽

Ning-Ning Jia ◽

Kuan Wang ◽

...

Keyword(s):

Mechanical Properties ◽

High Performance ◽

Mechanical Stability ◽

Gas Sensing ◽

Mechanical Analysis ◽

Sodium Ion ◽

Sodium Ion Batteries ◽

Tunnel Structure ◽

Gas Sensitivity ◽

Low Dimensional

Na2Ti7O15 (NTO) can be selected as candidate anode for high-performance sodium-ion batteries (SIBs). However, there are few reports of research on the mechanical properties of low-dimensional NTO, which is important for the stability of SIBs. In this work, by using the one-step hydrothermal method, NTO nanowires (NWs) with good orientation were prepared successfully. The transmission electron microscopy (TEM) and selected area electron diffraction (SAED)showed that the NTO NWs had a good aspect ratio and dispersion, with lengths over 20 μm. Further microstructure analysis showed that the nanowires grew along the (020) direction, and there were some "stripe" structures along the growing direction, which provides a good tunnel structure for Na ion channels. Further, the in situ mechanical analysis showed that the NTO NWs had excellent elastic deformation characteristics and mechanical structural stability. In addition, the NTO NWs also showed a good gas sensitivity to NO and NH3. Our results showed that the prepared NTO nanowires with a stripe tunnel oriented-structure and excellent mechanical properties may have a potential application in SIBs or other wearable sensor devices.

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Symmetry and reduction in collectives: low-dimensional cyclic pursuit

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2016.0465 ◽

2016 ◽

Vol 472 (2194) ◽

pp. 20160465 ◽

Cited By ~ 2

Author(s):

Kevin S. Galloway ◽

Eric W. Justh ◽

P. S. Krishnaprasad

Keyword(s):

Closed Loop ◽

Physical Space ◽

Relative Equilibria ◽

Two Dimensions ◽

Three Dimensions ◽

Control Schemes ◽

Loop Dynamics ◽

Cyclic Pursuit ◽

Steering Law ◽

Low Dimensional

We investigate low-dimensional examples of cyclic pursuit in a collective, wherein each agent employs a constant bearing (CB) steering law relative to exactly one other agent. For the case of three agents in the plane, we characterize relative equilibria and pure shape equilibria of associated closed-loop dynamics. Re-scaling time yields a reduction of phase space to two dimensions and effective tools for stability analysis. Study of bifurcation of a family of collinear equilibria dependent on a single CB control parameter reveals the presence of a rich collection of trajectories that are periodic in shape and undergo precession in physical space. For collectives in three dimensions, with an appropriate notion of CB pursuit strategy and corresponding steering law, the two-agent case proves to be explicitly integrable. These results suggest control schemes for small teams of mobile robotic agents engaged in area coverage tasks such as search and rescue, and raise interesting possibilities for behaviour in biological contexts.

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Low dimensional structures and devices: micro- and nano-technology

Microelectronics Journal ◽

10.1016/s0026-2692(96)00065-1 ◽

1997 ◽

Vol 28 (4) ◽

pp. 367-370

Author(s):

M. Henini ◽

J.M. Karam

Keyword(s):

Nano Technology ◽

Low Dimensional

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Thirty Years in Silicon Photonics: A Personal View

Frontiers in Physics ◽

10.3389/fphy.2021.786028 ◽

2021 ◽

Vol 9 ◽

Author(s):

Lorenzo Pavesi

Keyword(s):

Optical Networks ◽

Silicon Photonics ◽

Light Propagation ◽

Gas Sensing ◽

Single Photon ◽

Optical Signal ◽

Research Field ◽

Microring Resonators ◽

Personal View ◽

Low Dimensional

Silicon Photonics, the technology where optical devices are fabricated by the mainstream microelectronic processing technology, was proposed almost 30 years ago. I joined this research field at its start. Initially, I concentrated on the main issue of the lack of a silicon laser. Room temperature visible emission from porous silicon first, and from silicon nanocrystals then, showed that optical gain is possible in low-dimensional silicon, but it is severely counterbalanced by nonlinear losses due to free carriers. Then, most of my research focus was on systems where photons show novel features such as Zener tunneling or Anderson localization. Here, the game was to engineer suitable dielectric environments (e.g., one-dimensional photonic crystals or waveguide-based microring resonators) to control photon propagation. Applications of low-dimensional silicon raised up in sensing (e.g., gas-sensing or bio-sensing) and photovoltaics. Interestingly, microring resonators emerged as the fundamental device for integrated photonic circuit since they allow studying the hermitian and non-hermitian physics of light propagation as well as demonstrating on-chip heavily integrated optical networks for reconfigurable switching applications or neural networks for optical signal processing. Finally, I witnessed the emergence of quantum photonic devices, where linear and nonlinear optical effects generate quantum states of light. Here, quantum random number generators or heralded single-photon sources are enabled by silicon photonics. All these developments are discussed in this review by following my own research path.

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Review lecture - Quantum processes in semiconductor structures

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1988.0115 ◽

1988 ◽

Vol 420 (1858) ◽

pp. 1-19 ◽

Cited By ~ 12

Keyword(s):

Electron Scattering ◽

Low Temperatures ◽

Quantum Interference ◽

Short Review ◽

Two Dimensions ◽

Quantum Processes ◽

Semiconductor Structures ◽

Scattering Rate ◽

Effect Of Disorder ◽

Effective Dimensionality

A short review is given on quantum interference and interaction effects in semiconductor structures. It is shown that these effects give rise to observable corrections in the conductivity at low temperatures and can be separated by the behaviour of the magnetoresistance. Results are presented on the dimensionality dependence of the interference and it is shown that when a magnetic field determines the magnitude of the effect, this can be used to change the effective dimensionality of the system. The use of magnetoresistance in the extraction of electron–electron scattering rates is discussed and it is shown that in two dimensions the effect of disorder on the electron–electron scattering rate can be observed.

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Low-Dimensional Materials and State-of-the-Art Architectures for Infrared Photodetection

Sensors ◽

10.3390/s18124163 ◽

2018 ◽

Vol 18 (12) ◽

pp. 4163 ◽

Cited By ~ 7

Author(s):

Nasir Ilyas ◽

Dongyang Li ◽

Yuhao Song ◽

Hao Zhong ◽

Yadong Jiang ◽

...

Keyword(s):

State Of The Art ◽

Infrared Photodetectors ◽

Plasmonic Nanostructures ◽

Plasmonic Waveguides ◽

Practical Applications ◽

Military Applications ◽

Infrared Photodetection ◽

Photon Confinement ◽

Low Dimensional ◽

Low Dimensional Materials

Infrared photodetectors are gaining remarkable interest due to their widespread civil and military applications. Low-dimensional materials such as quantum dots, nanowires, and two-dimensional nanolayers are extensively employed for detecting ultraviolet to infrared lights. Moreover, in conjunction with plasmonic nanostructures and plasmonic waveguides, they exhibit appealing performance for practical applications, including sub-wavelength photon confinement, high response time, and functionalities. In this review, we have discussed recent advances and challenges in the prospective infrared photodetectors fabricated by low-dimensional nanostructured materials. In general, this review systematically summarizes the state-of-the-art device architectures, major developments, and future trends in infrared photodetection.

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