Integrated nano-optomechanical displacement sensor with ultrawide optical bandwidth

Abstract Optical read-out of motion is widely used in sensing applications. Recent developments in micro- and nano-optomechanical systems have given rise to on-chip mechanical sensing platforms, potentially leading to compact and integrated optical motion sensors. However, these systems typically exploit narrow spectral resonances and therefore require tuneable lasers with narrow linewidth and low spectral noise, which makes the integration of the read-out extremely challenging. Here, we report a step towards the practical application of nanomechanical sensors, by presenting a sensor with ultrawide (∼80 nm) optical bandwidth. It is based on a nanomechanical, three-dimensional directional coupler with integrated dual-channel waveguide photodiodes, and displays small displacement imprecision of only 45 fm/Hz1/2 as well as large dynamic range (>30 nm). The broad optical bandwidth releases the need for a tuneable laser and the on-chip photocurrent read-out replaces the external detector, opening the way to fully-integrated nanomechanical sensors.

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Rapid Growth of TiO2 Nanoflowers via Low-Temperature Solution Process: Photovoltaic and Sensing Applications

Materials ◽

10.3390/ma12040566 ◽

2019 ◽

Vol 12 (4) ◽

pp. 566 ◽

Cited By ~ 7

Author(s):

M. Akhtar ◽

Ahmad Umar ◽

Swati Sood ◽

InSung Jung ◽

H. Hegazy ◽

...

Keyword(s):

Low Temperature ◽

Anatase Phase ◽

Three Dimensional ◽

Solution Process ◽

Dye Sensitized Solar Cell ◽

Sensor Applications ◽

Dye Sensitized ◽

Sensing Applications ◽

Density Growth ◽

Temperature Solution

This paper reports the rapid synthesis, characterization, and photovoltaic and sensing applications of TiO2 nanoflowers prepared by a facile low-temperature solution process. The morphological characterizations clearly reveal the high-density growth of a three-dimensional flower-shaped structure composed of small petal-like rods. The detailed properties confirmed that the synthesized nanoflowers exhibited high crystallinity with anatase phase and possessed an energy bandgap of 3.2 eV. The synthesized TiO2 nanoflowers were utilized as photo-anode and electron-mediating materials to fabricate dye-sensitized solar cell (DSSC) and liquid nitroaniline sensor applications. The fabricated DSSC demonstrated a moderate conversion efficiency of ~3.64% with a maximum incident photon to current efficiency (IPCE) of ~41% at 540 nm. The fabricated liquid nitroaniline sensor demonstrated a good sensitivity of ~268.9 μA mM−1 cm−2 with a low detection limit of 1.05 mM in a short response time of 10 s.

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Electromechanically reconfigurable optical nano-kirigami

Nature Communications ◽

10.1038/s41467-021-21565-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Shanshan Chen ◽

Zhiguang Liu ◽

Huifeng Du ◽

Chengchun Tang ◽

Chang-Yin Ji ◽

...

Keyword(s):

Near Infrared ◽

Large Range ◽

Three Dimensional ◽

High Contrast ◽

Si Substrate ◽

High Modulation ◽

Gold Nanostructure ◽

Infrared Wavelengths ◽

On Chip ◽

Nano Electromechanical System

AbstractKirigami, with facile and automated fashion of three-dimensional (3D) transformations, offers an unconventional approach for realizing cutting-edge optical nano-electromechanical systems. Here, we demonstrate an on-chip and electromechanically reconfigurable nano-kirigami with optical functionalities. The nano-electromechanical system is built on an Au/SiO2/Si substrate and operated via attractive electrostatic forces between the top gold nanostructure and bottom silicon substrate. Large-range nano-kirigami like 3D deformations are clearly observed and reversibly engineered, with scalable pitch size down to 0.975 μm. Broadband nonresonant and narrowband resonant optical reconfigurations are achieved at visible and near-infrared wavelengths, respectively, with a high modulation contrast up to 494%. On-chip modulation of optical helicity is further demonstrated in submicron nano-kirigami at near-infrared wavelengths. Such small-size and high-contrast reconfigurable optical nano-kirigami provides advanced methodologies and platforms for versatile on-chip manipulation of light at nanoscale.

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1.0 V-0.18 µm CMOS Tunable Low Pass Filters with 73 dB DR for On-Chip Sensing Acquisition Systems

Electronics ◽

10.3390/electronics10050563 ◽

2021 ◽

Vol 10 (5) ◽

pp. 563

Author(s):

Jorge Pérez-Bailón ◽

Belén Calvo ◽

Nicolás Medrano

Keyword(s):

Power Consumption ◽

Dynamic Range ◽

Low Voltage ◽

Cutoff Frequency ◽

Cmos Technology ◽

Active Area ◽

Current Steering ◽

Low Pass ◽

On Chip ◽

Low Pass Filters

This paper presents a new approach based on the use of a Current Steering (CS) technique for the design of fully integrated Gm–C Low Pass Filters (LPF) with sub-Hz to kHz tunable cut-off frequencies and an enhanced power-area-dynamic range trade-off. The proposed approach has been experimentally validated by two different first-order single-ended LPFs designed in a 0.18 µm CMOS technology powered by a 1.0 V single supply: a folded-OTA based LPF and a mirrored-OTA based LPF. The first one exhibits a constant power consumption of 180 nW at 100 nA bias current with an active area of 0.00135 mm2 and a tunable cutoff frequency that spans over 4 orders of magnitude (~100 mHz–152 Hz @ CL = 50 pF) preserving dynamic figures greater than 78 dB. The second one exhibits a power consumption of 1.75 µW at 500 nA with an active area of 0.0137 mm2 and a tunable cutoff frequency that spans over 5 orders of magnitude (~80 mHz–~1.2 kHz @ CL = 50 pF) preserving a dynamic range greater than 73 dB. Compared with previously reported filters, this proposal is a competitive solution while satisfying the low-voltage low-power on-chip constraints, becoming a preferable choice for general-purpose reconfigurable front-end sensor interfaces.

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High-Performance On-Chip Silicon Beamsplitter Based on Subwavelength Metamaterials for Enhanced Fabrication Tolerance

Nanomaterials ◽

10.3390/nano11051304 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1304

Author(s):

Raquel Fernández de Cabo ◽

David González-Andrade ◽

Pavel Cheben ◽

Aitor V. Velasco

Keyword(s):

Integrated Circuits ◽

Fundamental Mode ◽

High Performance ◽

Three Dimensional ◽

High Sensitivity ◽

Power Splitting ◽

Excess Loss ◽

Power Splitters ◽

On Chip ◽

Efficient Power

Efficient power splitting is a fundamental functionality in silicon photonic integrated circuits, but state-of-the-art power-division architectures are hampered by limited operational bandwidth, high sensitivity to fabrication errors or large footprints. In particular, traditional Y-junction power splitters suffer from fundamental mode losses due to limited fabrication resolution near the junction tip. In order to circumvent this limitation, we propose a new type of high-performance Y-junction power splitter that incorporates subwavelength metamaterials. Full three-dimensional simulations show a fundamental mode excess loss below 0.1 dB in an ultra-broad bandwidth of 300 nm (1400–1700 nm) when optimized for a fabrication resolution of 50 nm, and under 0.3 dB in a 350 nm extended bandwidth (1350–1700 nm) for a 100 nm resolution. Moreover, analysis of fabrication tolerances shows robust operation for the fundamental mode to etching errors up to ± 20 nm. A proof-of-concept device provides an initial validation of its operation principle, showing experimental excess losses lower than 0.2 dB in a 195 nm bandwidth for the best-case resolution scenario (i.e., 50 nm).

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A new efficient multi‐task applications mapping for three‐dimensional Network‐on‐Chip based MPSoC

Concurrency and Computation Practice and Experience ◽

10.1002/cpe.6194 ◽

2021 ◽

Author(s):

Khadidja Gaffour ◽

Mohammed Kamel Benhaoua ◽

Abou El Hassan Benyamina ◽

Amit Kumar Singh

Keyword(s):

Three Dimensional ◽

Network On Chip ◽

Dimensional Network ◽

On Chip

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Foundations of Advanced Neuroanatomy: Technical Guidelines for Specimen Preparation, Dissection, and 3D-Photodocumentation in a Surgical Anatomy Laboratory

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0039-3399590 ◽

2019 ◽

Author(s):

Luciano César PC Leonel ◽

Lucas P. Carlstrom ◽

Christopher S. Graffeo ◽

Avital Perry ◽

Carlos Diogenes Pinheiro-Neto ◽

...

Keyword(s):

Oral Tradition ◽

Dynamic Range ◽

Tap Water ◽

Three Dimensional ◽

High Dynamic Range ◽

Surgical Anatomy ◽

Lessons Learned ◽

Specimen Preparation ◽

Technological Advances ◽

Key Steps

Abstract Objective This study was aimed to provide a key update to the seminal works of Prof. Albert L. Rhoton Jr., MD, with particular attention to previously unpublished insights from the oral tradition of his fellows, recent technological advances including endoscopy, and high-dynamic range (HDR) photodocumentation, and, local improvements in technique, we have developed to optimize efficient neuroanatomic study. Methods Two formaldehyde-fixed cadaveric heads were injected with colored latex to demonstrate step-by-step specimen preparation for microscopic or endoscopic dissection. One formaldehyde-fixed brain was utilized to demonstrate optimal three-dimensional (3D) photodocumentation techniques. Results Key steps of specimen preparation include vessel cannulation and securing, serial tap water flushing, specimen drainage, vessel injection with optimized and color-augmented latex material, and storage in 70% ethanol. Optimizations for photodocumentation included the incorporation of dry black drop cloth and covering materials, an imaging-oriented approach to specimen positioning and illumination, and single-camera stereoscopic capture techniques, emphasizing the three-exposure-times-per-eye approach to generating images for HDR postprocessing. Recommended tools, materials, and technical nuances were emphasized throughout. Relative advantages and limitations of major 3D projection systems were comparatively assessed, with sensitivity to audience size and purpose specific recommendations. Conclusion We describe the first consolidated step-by-step approach to advanced neuroanatomy, including specimen preparation, dissection, and 3D photodocumentation, supplemented by previously unpublished insights from the Rhoton fellowship experience and lessons learned in our laboratories in the past years such that Prof. Rhoton's model can be realized, reproduced, and expanded upon in surgical neuroanatomy laboratories worldwide.

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Ab initiostructure determination of nanocrystals of organic pharmaceutical compounds by electron diffraction at room temperature using a Timepix quantum area direct electron detector

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273315022500 ◽

2016 ◽

Vol 72 (2) ◽

pp. 236-242 ◽

Cited By ~ 73

Author(s):

E. van Genderen ◽

M. T. B. Clabbers ◽

P. P. Das ◽

A. Stewart ◽

I. Nederlof ◽

...

Keyword(s):

Electron Diffraction ◽

Room Temperature ◽

Dynamic Range ◽

Signal To Noise Ratio ◽

Three Dimensional ◽

Direct Methods ◽

Liquid Nitrogen Temperature ◽

High Dynamic Range ◽

Electron Diffraction Data ◽

High Signal

Until recently, structure determination by transmission electron microscopy of beam-sensitive three-dimensional nanocrystals required electron diffraction tomography data collection at liquid-nitrogen temperature, in order to reduce radiation damage. Here it is shown that the novel Timepix detector combines a high dynamic range with a very high signal-to-noise ratio and single-electron sensitivity, enablingab initiophasing of beam-sensitive organic compounds. Low-dose electron diffraction data (∼0.013 e− Å−2 s−1) were collected at room temperature with the rotation method. It was ascertained that the data were of sufficient quality for structure solution using direct methods using software developed for X-ray crystallography (XDS,SHELX) and for electron crystallography (ADT3D/PETS,SIR2014).

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