Effective Evaluation of the Noise Factor of Microchannel Plate

To improve the noise performance of microchannel plate (MCP), we have presented a method using the sine random signals with Poisson distribution as the noise-excitation for electron source. By using this method, the effective evaluation of noise characteristics of MCP has been implemented through measuring and analyzing its noise factor. The results have demonstrated that the noise factor of filmed MCP is lower than 1.8. Additionally, as the open area ratio and the input electron energy are 72% and 400 eV, respectively, the noise characteristics of unfilmed MCP are improved evidently. Moreover, larger open area ratio, higher input electron energy, and higher voltage across the MCP all can reduce effectively the noise factor within a certain range. Meanwhile, the ion barrier film extends the life of image tube but at the cost of an increased noise factor. Therefore, it is necessary that a compromise between the optimum thickness of ion barrier film, open area ratio, input electron energy, and voltage across the MCP must be reached.

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Influence of MCP open area ratio and secondary electron emission layer on noise factor of image intensifier tubes

Seventh Symposium on Novel Photoelectronic Detection Technology and Applications ◽

10.1117/12.2587353 ◽

2021 ◽

Author(s):

Jinneng Zeng ◽

Tingtao Li ◽

Heng Zhao ◽

Le Chang ◽

Yanni Gong ◽

...

Keyword(s):

Electron Emission ◽

Secondary Electron ◽

Secondary Electron Emission ◽

Image Intensifier ◽

Area Ratio ◽

Noise Factor ◽

Open Area ◽

Emission Layer

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Multiple Quantum Barrier Nano-avalanche Photodiodes - Part II: Excess Noise Characteristics

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666180813123035 ◽

2019 ◽

Vol 9 (2) ◽

pp. 185-191

Author(s):

Somrita Ghosh ◽

Aritra Acharyya

Keyword(s):

Avalanche Photodiodes ◽

Noise Factor ◽

Excess Noise ◽

Multiple Quantum ◽

Noise Performance ◽

Excess Noise Factor ◽

Simulation Methodology ◽

Noise Characteristics ◽

Good Agreement ◽

Ionization Rates

Background: Excess noise characteristics of Multiple Quantum Barrier (MQB) nanoscale avalanche photodiodes (APDs) based on Si~3C-SiC heterostructures have been studied in this part of the paper. The multiplication gain and Excess Noise Factor (ENF) of the MQB APDs have been calculated by varying the number of Quantum Barriers (QBs). Methods: The numerically calculated ENF values of MQB APDs have been compared with the ENF of Si flat conventional APDs of similar dimensions and it is observed that the use of QBs leads to significant reduction in ENF of the APDs under similar biasing and illumination conditions. Results: The enhanced ratio of hole to electron ionization rates in MQB structures as compared to the bulk Si APD structure has been found to be the primary cause of improvement in the noise performance of the MQB nano-APDs. Conclusion: Finally, the numerically calculated ENF of Si flat APD has been compared with the experimentally measured ENF of a commercially available Si APD and those are found to be in good agreement; this comparison validates the simulation methodology adopted by the authors in this paper.

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Noise factor of microchannel plate with ion barrier film

10.1117/12.977793 ◽

2012 ◽

Author(s):

Shu-lin Liu ◽

Feng Shi ◽

Zhou-kui Li ◽

Yu-feng Zhu ◽

Ni Zhang ◽

...

Keyword(s):

Microchannel Plate ◽

Noise Factor ◽

Barrier Film

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Influence of Resonances on the Noise Performance of SQUID Susceptometers

Sensors ◽

10.3390/s20010204 ◽

2019 ◽

Vol 20 (1) ◽

pp. 204 ◽

Cited By ~ 1

Author(s):

Samantha I. Davis ◽

John R. Kirtley ◽

Kathryn A. Moler

Keyword(s):

Quantum Interference ◽

Noise Performance ◽

Superconducting Quantum Interference Device ◽

Noise Characteristics ◽

Current Voltage ◽

Electromagnetic Resonances ◽

Current Voltage Characteristics ◽

Local Magnetic Fields ◽

Scanning Squid ◽

Further Development

Scanning Superconducting Quantum Interference Device (SQUID) Susceptometry simultaneously images the local magnetic fields and susceptibilities above a sample with sub-micron spatial resolution. Further development of this technique requires a thorough understanding of the current, voltage, and flux ( I V Φ ) characteristics of scanning SQUID susceptometers. These sensors often have striking anomalies in their current–voltage characteristics, which we believe to be due to electromagnetic resonances. The effect of these resonances on the performance of these SQUIDs is unknown. To explore the origin and impact of the resonances, we develop a model that qualitatively reproduces the experimentally-determined I V Φ characteristics of our scanning SQUID susceptometers. We use this model to calculate the noise characteristics of SQUIDs of different designs. We find that the calculated ultimate flux noise is better in susceptometers with damping resistors that diminish the resonances than in susceptometers without damping resistors. Such calculations will enable the optimization of the signal-to-noise characteristics of scanning SQUID susceptometers.

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Impact of Tile Design on Thermal Performance of Open and Enclosed Aisles

ASME 2017 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems ◽

10.1115/ipack2017-74339 ◽

2017 ◽

Author(s):

Sadegh Khalili ◽

Mohammad I. Tradat ◽

Kourosh Nemati ◽

Mark Seymour ◽

Bahgat Sammakia

Keyword(s):

Data Centers ◽

Area Ratio ◽

Inlet Temperature ◽

Open Area ◽

Cfd Simulations ◽

Physical Separation ◽

Hot Air ◽

Airflow Distribution ◽

The Impact ◽

Lower Noise

In raised floor data centers, tiles with high open area ratio or complex understructure are used to fulfill the demand of today’s high-density computing. Using more open tiles reduces pressure drop across the raised floor with the potential advantages of increased airflow and lower noise. However, it introduces the disadvantage of increased non-uniformity of airflow distribution. In addition, there are various tile designs available on the market with different opening shapes or understructures. Furthermore, a physical separation of cold and hot aisles (containment) has been introduced to minimize the mixing of cold and hot air. In this study, three types of floor tiles with different open area, opening geometry, and understructure are considered. Experimentally validated detail models of tiles were implemented in CFD simulations to address the impact of tile design on the cooling of IT equipment in both open and enclosed aisle configurations. Also, impacts of under-cabinet leakage on the IT equipment inlet temperature in the provisioned and under-provisioned scenarios are studied. Finally, a predictive equation for the critical under-provisioning point that can lead to a no-flow condition in IT equipment with weaker airflow systems is presented.

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Effect of ion barrier film on the noise characteristics of proximity focusing low-light-level image intensifier

10.1117/12.2032298 ◽

2013 ◽

Author(s):

De Song ◽

Chunyang Liu ◽

Xulei Qin ◽

Shanshan Yu ◽

Kuncheng Fu ◽

...

Keyword(s):

Image Intensifier ◽

Light Level ◽

Low Light ◽

Noise Characteristics ◽

Barrier Film

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New approach to noise factor measurement on microchannel plate of optoelectronic detector

10.1117/12.803618 ◽

2009 ◽

Author(s):

Lei Liu ◽

Yunsheng Qian ◽

Yafeng Qiu

Keyword(s):

Microchannel Plate ◽

Noise Factor ◽

New Approach ◽

Factor Measurement

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The Effectiveness of Film Cooling With Three-Dimensional Slot Geometries

Journal of Engineering for Power ◽

10.1115/1.3445602 ◽

1971 ◽

Vol 93 (4) ◽

pp. 425-430 ◽

Cited By ~ 8

Author(s):

M. N. R. Nina ◽

J. H. Whitelaw

Keyword(s):

Gas Turbine ◽

Wall Temperature ◽

Film Cooling ◽

Mass Velocity ◽

Three Dimensional ◽

Area Ratio ◽

Hole Injection ◽

Open Area ◽

Adiabatic Wall

The paper describes measurements of adiabatic wall temperature downstream of discrete hole injection slots for a range of parameters relevant to gas turbine practice. The influence of open-area-ratio, slot-lip-length and slot-lip-thickness is determined for tangential holes and a range of mass velocity ratios, 0.3 < m < 2.0, and downstream distances up to 40 equivalent slot heights; similar measurements are reported downstream of three-dimensional splash cooling geometries. In all, 13 different three-dimensional configurations are investigated and permit conclusions to be drawn as to the significance of the parameters investigated. The measurements clearly demonstrate the need for a thin and long slot lip and for a large value of open area ratio.

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