Quantum computer is expected to come true! Stanford has developed room temperature chip materials
Abstract: Elaine wokovich, a professor of electronic engineering at Stanford University, led his team, recently published three papers in the magazine, claiming that they have developed quantum chip materials that can operate at room temperature, including a quantum dot and two "color centers", making quantum processing devices a big step towards practical application
Elena wokovic, a professor of electronic engineering at Stanford University, led her team, recently published three papers in the magazine, claiming that they have developed quantum chip materials that can operate at room temperature, including a quantum dot and two "color centers", making quantum processing devices a big step towards practical application
it is understood that in the existing quantum computing technology, some cutting-edge research needs to cool the material to about absolute zero (-273.15 ℃), which hinders the process of quantum computer from theory to practice. In order to solve this problem, scientists began to seek to replace traditional silicon-based computers with photon based quantum computers. Quantum computers can perform various complex calculations faster, study biological systems, create encryption and big data systems, and solve many problems involving multiple variables
looking for a needle in the sea: quantum computers are not afraid.
as a frontier scientist in the field of quantum computers, wokovic said: "when people think that something is impossible, they like to use 'looking for a needle in the sea', but quantum computing can do it." The reason why quantum computers have such powerful capabilities lies in the complexity of the interaction between lasers and electrons, which is the most critical technology
the working principle of quantum computer is to enclose spin electrons in a new type of semiconductor material. When laser irradiates them, laser can interact with electrons to make electrons present different spin states. Traditional computers run on binary systems based on numbers 0 and 1; Quantum computer is based on quantum bits. These qubits represent the two states of 0 and 1, and can be any value between 0 and 1. "In a quantum system, the impact of a laser on an electron can create many possible spin states. The more spin states, the more complex quantum calculations can be performed," Walker said
in the past 20 years, wachovik laboratory has been focusing on the development of quantum chips that can operate at room temperature. Recently, they cooperated with other laboratories to test three kinds of materials. The results showed that one of the materials could operate at room temperature, which made the quantum computer take an important step, and it was no longer just "paper 6. Deformation accuracy: better than 1%
new quantum dots: accurately control the input and output of photons
volkovic team has developed three basic functional units based on three different materials, which are similar to the transistors in traditional silicon-based chips. Based on semiconductor crystal materials, they created a structural unit that can "confine" a single spin electron by adjusting the atomic array in the crystal
the first structure is quantum dots, and relevant papers have been published in the journal Nature Physics. Quantum dots are spherical or hemispherical structures made of semiconductor materials with a diameter of less than 20 nm. They are tiny dots in appearance and can enclose spin electrons in nanospheres. They doped a small amount of indium arsenide into gallium arsenide crystal to make quantum dots, which can successfully control the input and output of photons through laser electron interaction. Moreover, unlike previous single photons, this time the photons can come out in pairs. Wokovic said that compared with those quantum computer platforms that need low-temperature refrigeration, their quantum dots are more practical. Although they cannot be used to create general-purpose quantum computers at present, they can be used to create secure communication networks that prevent tampering
two kinds of "color centers": breakthroughs from low temperature to room temperature
in another two papers published in the Journal of nano communication, wachovik team introduced a completely different method from quantum dots: capturing electrons with "color center" technology. Color center refers to the point defects, point defect pairs or point defect groups in transparent crystals. These defects can capture electrons or holes, absorb photons and make the crystal show different colors
the color center described in a paper is constructed in diamonds. The lattice of natural diamonds is composed of carbon atoms, but they use silicon atoms to replace some carbon atoms in diamonds, creating multiple color centers in the diamond lattice. These diamond color centers can efficiently capture spin electrons, but they still need to be cooled to a certain temperature
wokovic also worked with other teams to develop a third material - highly modified silicon carbide color center. They described the test results of this material in another paper. Silicon carbide is a hard and transparent crystal, which is often used to make clutch plates, brake pads and bulletproof vests. Previous studies have reported that the modified silicon carbide can be made into color centers that work at room temperature, but the efficiency is not high, so it can not be used to develop quantum chips. By knocking out some silicon atoms in silicon carbide, the wokovic team developed a high-efficiency color center. Then, they added nanowire structure around the color center, which greatly improved the ability of color center to capture electronsThe recovery of the international market
Walker said that the high-efficiency color center they developed can be operated at room temperature, which is a breakthrough in the field of quantum computer research and provides a practical method for the development of quantum chips. But she also said: otherwise, the ring should be hung on the key blade. "We still need to continue to study which of these three materials will eventually stand out."