Maximum Theoretical Limit For Optoelectronic Devices

Researchers have calculated the maximum theoretical limit for optoelectronic devices, the point at which the laws of quantum mechanics prevent microchips from becoming any faster.

Optoelectronics are the fastest devices globally — systems that use light to control electricity. The new study outlines the limit for optoelectronics by calculating the speed at which the most potent examples of these devices can operate (maximum theoretical limit).

To make their calculations, the team experimented with semiconductor materials and lasers. A quick laser pulse energizes electrons in the material before a second, slightly longer lase pulse produces an electrical current in the material. The researchers observed the current while applying shorter and shorter laser pulses until Heisenberg’s uncertainty principle allowed them to go no further. Heisenberg’s uncertainty principle states that the more accurately you measure one variable of a particle, such as its position, the more uncertain other variables, such as momentum, will be, and vice versa.

So, according to the researchers, the maximum theoretical limit of optoelectronic systems is one Petahertz, which is equivalent to a million Gigahertz. To go any faster would be to break the laws of quantum physics.

Using shorter laser pulses meant the researchers could calculate exactly when the electrons gained energy. But, due to Heisenberg’s principle, this came at the cost of reduced certainty over the amount of energy gained.

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