Photon integrated circuit (FIS)

The technology of FIS production is similar to the technology used in the production of conventional integrated circuits - photolithography is used to mark the substrate. Components that may be present on the FIS include waveguide interconnects, power dividers, optical amplifiers, optical modulators, filters, lasers, and detectors. Today, optical integrated circuits have the widest application. A key area of ​ ​ their use, for which NeoPhotonics produces its equipment, are fiber-optic communication lines.

The use of FIS makes it possible to manufacture more compact and high-performance optical systems (compared to systems based on discrete optical components), and also provides the possibility of their integration with electronic circuits for miniaturization of multifunctional optical-electronic systems and devices.

One of the basic FIS-based devices is an optical splitter (splitter) - a passive device that separates the energy flow transmitted over the fiber. This device is passive because power is not required to separate the optical power.

Using optical splitters, it was possible to transmit a signal to several subscribers over one fiber, which made it possible to reduce the cost of building fiber-optic transmission lines (FOCL). This opportunity gave impetus to the development of passive optical networks (PON).

There are two main technologies for the manufacture of optical signal splitters and, accordingly, two types of optical splitters: planar optical splitters (English term Planar Lightwave Circuit splitter, PLC splitter) Alloy optical splitters (English term Fused Biconic Taper splitter, FBT splitter).

Planar splitters are produced by chemical deposition of optical material on quartz surface in several layers with etching at one stage through the mask of planar light guide of required configuration and optical density. The planar light guide is located between the plates of the optical material and plays the role of a core - optical power is transmitted through it. In fact, a crystal or chip is created consisting of a quartz plate and optical materials that ensure uniform separation of optical power and a Y-shaped optical splitter is created.

Photonic IT

Several attempts to create a photonic (optical) computer are known. In 1990, the layout of such a computer was demonstrated by Bell Labs, which finalized it by 1991 and presented it under the name DOC-II.

In 2003, Lenslet introduced the EnLight256 optical DSP processor, the core of which was created using optical technology, but the control was electronic.

In 2008, IBM demonstrated an optical switch on a chip based on silicon reflecting resonators. In 2009, MIT learned how to create waveguides directly on silicon chips.

2024: The assembly of a photon processor has begun in Russia, which accelerates neural networks hundreds of times

On August 9, 2024, it became known that the assembly of an experimental sample of a photon processor, which is able to speed up data processing in neural networks hundreds of times compared to modern semiconductor computers, had started in Russia. The assembly, which began in August 2024, is scheduled to be completed by the end of 2024. This project is being implemented at the Korolev Samara University as part of the scientific program of the National Center for Physics and Mathematics (NCPM) with the support of the state corporation Rosatom. Read more here.

2019: Russians find a cheap way to create microlasers for photon computers

An effective, fast and cheap way to create perovskite microlasers has been found - sources of intense light for optical microchips, which will then be used in next-generation computers. On March 13, 2019, TAdviser was reported at the Far Eastern Federal University. The technology was developed by FEFU scientists together with Russian colleagues from ITMO, scientists from the University of Texas Dallas and the Australian National University. An article about this was published in the scientific journal ACS Nano (impact factor 13).

Using ultrashort laser pulses, scientists printed optical microdisk lasers in thin perovskite films on a glass substrate. The obtained perovskite lasers can be used in computers of the future and more broadly - to ensure the operation of photon circuits in ultra-fast information processing devices, according to FEFU.

Scientists printed perovskite microlasers using ultrashort laser pulses

We used femtosecond laser pulses with a special bagel-shaped intensity profile. The direct effect of a series of such low energy pulses on a thin film of halide perovskite allows the formation of disks with a diameter of up to 2 microns with neat edges and minimal thermal effect on the perovskite material, which is important for the subsequent stable operation of the resulting laser. The original laser printing technology we developed allows us to quickly, low-cost and with a high degree of control produce microdisks of different diameters almost in conveyor mode, said Alexey Zhizhchenko, a researcher at the NTI FEFU Center for Virtual and Augmented Reality.

As the scientist emphasized, the optimization of the geometry of microdisks made by the laser printing method made it possible for the first time to obtain a perovskite microlaser that stably works in single-mode generation mode, that is, at the same wavelength. This, according to Alexei Zhizhchenko, makes them promising for the creation of photonic and optoelectronic nanodata, microsensors, etc.

In general, according to FEFU representatives, perovskite microlasers "demonstrate impressive performance, work at room temperature and are cheap to produce." However, earlier their manufacture was a certain challenge. The problem was the lack of efficient and low-cost production methods. For example, chemical synthesis does not guarantee the production of structures of the same size with controlled characteristics. Control is achieved using patterns produced by expensive nanolithography methods, the scientists explained. In addition, the parameters of perovskite microlasers demonstrated earlier did not allow for their single-mode operation. The original method of laser printing of perovskite disks, developed by FEFU and ITMO scientists in partnership with foreign colleagues, removes this restriction. According to experts, it makes it easy to create stable laser light sources with set, controlled parameters. According to their estimates, the technique can be put into production in the near future.

The achievements of the employees of the NTI FEFU center in virtual and augmented reality were the result of the implementation of the priority project "Materials." We managed to gather an active international team of world-class specialists, a significant part of which are young scientists under 30 years old, "said Kirill Golokhvast, Vice-Rector of FEFU for Scientific Work. - Laser studies of this level became possible thanks to the established femtosecond laser lithograph, as well as close cooperation between the FEFU and ITMO physics teams.

2016

Scientists were able to transmit information using a single photon

Princeton University scientists have developed a device that allows a single electron to transmit quantum information to a photon. The study was published in late 2016 in the journal Science and could be a real breakthrough in the field of quantum computer technology^[1].

"We now have the ability to directly transmit the quantum state to a photon. Previously, this was impossible to do using semiconductor devices, since the quantum state was lost before it could transmit information, "explained Princeton University scientist Xiao Mi

The device created by scientists is the result of five years of research and is a semiconductor chip consisting of silicon and silicon-germanium layers, on top of which there are nanowires. These wires are thinner than a human hair and are needed to deliver electricity to the chip. With it, scientists were able to capture the electron between silicon layers in microstructures known as quantum dots (fragments of a conductor or semiconductor whose charge carriers are limited in space across all three dimensions).

In this case, the electron plays the role of the smallest particle of information (bit). As a rule, the bit has one of two values ​ ​ - 1 or 0. However, in quantum computing, the smallest particles of information (qubits) can have two values ​ ​ at the same time. The ability to manipulate qubits significantly speeds up calculations, since the machine can solve not one, but several problems at the same time.

Scientists have chosen a photon as an intermediary between electrons because it is more resistant to external influences and can transmit information between quantum chips, and not just inside the chips of a single quantum chip.

Russians made it possible to create a photonic computer

Russian scientists have simulated an optical system that allows the signal to be transmitted almost without loss, which until now has been impossible in so-called plasmon and nanooptic devices. In the created model, small gain compensates for signal losses in waveguides. The discovery promises to revolutionize^[2] IT industry^[3] to^[4].

The study was conducted by employees of the Institute of Theoretical and Applied Electrodynamics of the Russian Academy of Sciences, the All-Russian Research Institute of Automation named after N. L. Dukhov and the Moscow Institute of Physics and Technology (MIPT). The results of the study were published in the journal Scientific Reports.

Waveguide system

During the study, scientists conducted a number of experiments with optical waveguides, which are used in fiber-optic communication lines. Despite the fact that the technology is already used to provide an Internet connection, its application at the microelectronic level is limited due to the problem of signal loss.

Schematic representation of a system of two waveguides with a periodically varying distance between them (Source: MIPT)

Scientists designed a system of two waveguides and began to affect its parameters, checking how this affects the signal. One waveguide had an absorbing medium, the second - an amplifying medium. Such a system is characterized by a change in the electromagnetic wave, which increases or decreases. This is because the wave that propagates in one waveguide interacts with the second.

As a result, the field flows from one waveguide to another, and the speed of its flow is greater the closer the waveguides are. If the maximum of the field is in the amplifying waveguide, the wave becomes more intense, if in the absorbing one - it subsides.

System Impact

During the experiment, scientists periodically changed the distance between waveguides, which influenced the flow of fields between them. Their task was to choose a distance change scheme in which the amplitude of the electromagnetic field will increase in both waveguides even when the losses in the first waveguide exceed the gain in the second.

Dependence of signal intensity (solid line) and field amplitude (dashed lines) in the first and second waveguides depending on the coordinate along them (Source: MIPT)

As a result, the researchers managed to change the distance between the waveguides at the peak of the system intensity so that the field concentrated in the waveguide with an amplifying medium. The consequence of this was the amplification of the signal. Theoretically, by changing the distance between waveguides, it is possible to infinitely increase power.

Scientists came to the conclusion that the parameters of the waveguides should be adjusted to the point of coincidence of wave modes, and then almost any change in parameters will entail the necessary redistribution of the field. The described scheme will also help in the fight against non-linear effects that suppress the increase in signal amplitude.

Using this method, it is possible to achieve a constant stable signal in photonic circuits, which will make photonic computers a reality. Signal transmission by photons is much faster than by electrons, since the speed of photons is equal to the speed of light.

See also

• Rusnano Neophotonics
• Quantum Computers and Quantum Communications
• Quantum cryptography (encryption)
• Russian Quantum Center (RCC, Russian Quantum Center, RQC)
• Supercomputer

Notes