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Successfully developed an imaginary-time evolution method that runs only on a quantum computer

Quemix has developed a quantum algorithm for probabilistic imaginary-time evolution using a quantum computer. The successful development of this quantum algorithm has opened up the possibility of a new quantum chemical calculation method. (

The imaginary-time evolution method is an algorithm that has long been known as an excellent algorithm for combinatorial optimization and quantum chemical calculations. In addition, the imaginary-time evolution method has the potential to bring out the performance of quantum computers, and it has become an algorithm that attracts a great deal of attention on quantum computers. However, since the imaginary-time evolution algorithms proposed so far for quantum computers use a hybrid algorithm with a classical computer, the classical computer has a problem of slowing down the computation speed.

Now, Quemix has successfully developed a probabilistic imaginary-time evolution method that can perform imaginary-time evolution on a quantum computer alone. We have shown that the number of quantum auxiliary bits required to perform the calculation can be minimized. This makes it possible to perform the imaginary-time evolution method away from the rate-limiting speed of a classical computer, and to extract the full performance of a quantum computer.

By successfully developing this quantum algorithm, we have shown the possibility of a new quantum chemical calculation method that is not based on the variational principle. The new method is a quantum chemical calculation method (FQE) that employs the probabilistic imaginary-time evolution method and the first quantization form, and is the first to demonstrate the possibility of significantly reducing the computational cost and achieving higher accuracy than previously proposed quantum chemical calculation methods.

Quemix will continue to develop new quantum algorithms and methods to calculate materials.



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