Neurotransmitter

A transistor "neuron" has been created, behaving exactly like its living counterpart

DailyTechInfo based on materials Phys.org : Neuron transistor behaves like a brain neuron

Researchers from the Chinese University of Electronic Science and Technology (University of Electronic Science and Technology) and Nanyang Technological University (Nanyang Technological University), Singapore, have created the first of its kind "transistor neuron", a semiconductor device that behaves exactly like a neuron of living nerve tissues. Such devices can become one of the types of future neuromorphic processors, on the basis of which computing systems will be created that work in the same way as the human brain. And, as is well known, such systems are ideal for solving problems of a certain class, such as adaptation, machine vision and deep learning.

In order for a conventional transistor to behave like a neuron, it requires the ability to implement some basic "neural" functions, such as weighted summation and calculation of threshold functions. It is these functions that underlie the work of a living neuron, which is able to receive many signals from other neurons, sum them up, and when a certain threshold of the summed signal is exceeded, it triggers itself. Billions of neurons in the human brain constantly perform summation and calculation of threshold functions many times per second, and all this together gives us the opportunity to think and control our actions.

As mentioned above, researchers have created a "neural transistor" or "transistor neuron", which is capable of performing the functions of summing signals and calculating threshold values. This transistor is not made of traditional silicon, but of a two-dimensional layer of molybdenum disulfide (MoS ₂, molybdenum), a material belonging to a new class of semiconductors called transition metal dichalcogenides.

This transistor has two control electrodes, gates, and it is possible to control the operation of the transistor both with the help of each of the gates separately, and with the help of two gates at the same time. In the latter case, the transistor performs the function of summing signals. In their research, scientists have demonstrated that the semiconductor device they created is capable of performing a number of other logical operations using a certain combination of signals on the control electrodes.

One of the advantages of the new "transistor neuron" is the speed of its operation. Note that this case is not the first case of the creation of such semiconductor devices, but all previously created such devices could operate at a speed of 0.05 Hz. The new "transistor neuron" is capable of operating at speeds from 0.01 to 15 Hz, which will allow in the future to create a number of high-speed neuromorphic hardware based on it. For comparison, brain neurons work at an average speed of 5 Hz.

In the near future, the researchers plan to add several additional control electrodes to the structure of the "transistor neuron", which will allow them to obtain a more realistic analogue of a living neuron with a large number of "ports" for input signals. In addition, the researchers plan to combine such a multi-gate transistor with a memristor, an electronic component that will act as an artificial synapse.

Portal "Eternal youth" http://vechnayamolodost.ru  05.07.2017