English

2D photoelectric neuron array can achieve broadband and low loss optical nonlinearity accessible to ambient light

1044
2024-03-20 15:47:32
See translation

Light can calculate functions during propagation and interaction with structured materials, with fast speed and low energy consumption. The use of all optical neural networks for general computing requires an optical activation layer with nonlinear dependence on the input. However, existing optical nonlinear materials either have slow speeds or very weak nonlinearity at the level of natural light intensity captured by cameras. Therefore, designing and developing new optical activation functions is crucial for achieving optical neural networks that utilize ambient light for computation.

In a paper published in Nature Communications, a research team led by Professor Duan Xiangfeng and Professor Aydogan Ozcan from the University of California, Los Angeles reported a new strategy using a photonic neuron array to achieve strong optical nonlinearity for broadband incoherent light at low light intensity.

Their devices are heterogeneous and integrated with two-dimensional transparent phototransistors and liquid crystal modulators. Under weak light irradiation, TPT has high electrical resistance, and most of the voltage drop occurs on TPT. LC is not disturbed and maintains transparency. However, at high input optical power, TPT becomes conductive, causing most of the voltage to drop on the LC layer, thereby cutting off optical transmission.

In their experimental demonstration, the designed photoelectric neuron allowed for nonlinear modulation of its own amplitude by spatially and temporally incoherent light in visible light wavelengths, with photon loss of only~20%. They created a 100x100 array of photoelectric neurons and exhibited strong nonlinear behavior under laser and white light irradiation.

The nonlinear photoelectric array is further integrated as part of the mobile phone based imaging system, used for intelligent reduction of glare, selective blocking of strong glare, and almost no attenuation of objects with weaker intensity in the imaging field of view.

Device modeling shows that the optical intensity threshold is very low, only 56 μ W/cm2 produces significant nonlinear response for optimized devices, and the energy consumption per photon activation is as low as 69 fJ.

This photoelectric neuron array can perform nonlinear self amplitude modulation on spatially incoherent light, with characteristics such as low light intensity threshold, strong nonlinear contrast, wide spectral response, fast speed, and low photon loss. For image processing and visual computing systems that do not rely on strong laser beams, this performance is very ideal.

In addition to intelligent glare reduction, the cascaded integration of photoelectric neuron arrays and linear diffraction optical processors can be used to construct nonlinear optical networks, which may be widely used in computational imaging and sensing, and also open the door to the design of new nonlinear optical processors that use ambient light.

Source: Laser Net

Related Recommendations
  • The world's most powerful laser attempts to unravel the secrets of the universe

    They are the strongest lasers in history, and their beams are helping scientists explore the structure of the universe.In a research laboratory at the University of Michigan, bright green light fills the vacuum chamber of a technology giant. It is the size of two tennis courts. The walls are shielded with 60 centimeters of concrete to prevent radiation leakage, and workers wear masks and hairnets ...

    2023-11-28
    See translation
  • New Progress: III-V Laser and Silicon Optics Technology Achieve Single Chip High Integration

    Recently, Scientific Photonics, a supplier of silicon photonic integrated circuits (PICs) headquartered in Grenoble, announced that it has successfully integrated III-V-DFB lasers and amplifiers with standard silicon photonic technology into the production process of Tower Semiconductor.By utilizing proprietary technology and standard silicon photonics, Scientific Photonics has achieved full inte...

    2024-03-01
    See translation
  • The world's first 40000 watt groove laser cutting machine is put into production in China

    On the morning of August 26th, the world's first large-scale 40000 watt groove laser cutting machine production ceremony was successfully held at Shandong Century Zhenghua Metal Technology Co., Ltd. located in Zhoucun District, adding another boost to the rapid development of Zhoucun's stainless steel industry chain.Source:博览新闻

    2023-08-28
    See translation
  • This laser cleaning "dark horse" announces annual performance and shareholder information

    On April 15th local time, Laser Photonics, a developer of laser cleaning equipment and solutions, announced its financial results for the fourth quarter and the year ended December 31, 2023. The financial report shows that in the fourth quarter of 2023, its revenue was $800000, with reduced operating and net losses. Here are the specific data:In addition to the financial report, the company's CEO ...

    2024-04-16
    See translation
  • Shanghai Optical and Mechanical Institute has made progress in ultra-low threshold Rydberg state single mode polariton lasers based on symmetric engineering

    Recently, the research team of Dong Hongxing and Zhang Long from the Research Center of Infrared Optical Materials of the Chinese Academy of Sciences Shanghai Institute of Optics and Precision Mechanics, in cooperation with Huazhong University of Science and Technology, reported a new mechanism for generating dynamically tunable single-mode lasers from exciton polaritons with ultra-low thresholds,...

    2023-10-12
    See translation