Yu Tanaka of the Advanced Research Laboratory of Sony Group Corporation gave two poster presentations on joint research projects in the area of quantum information theory at the international conference on Quantum Information Processing (QIP 2024) held in Taipei.
Achievements of the joint research project with the Murao Group of the University of Tokyo)
Quantum state preparation (QSP) is the task of preparing a quantum state for a given classical description of the quantum state. It is used as a subroutine of many quantum algorithms. Since general-purpose QSP methods are known to require high computing costs, various other QSP techniques have been proposed that prepare fewer types of quantum states to reduce the required amount of computation. We have proved that, when the quantum state to be prepared has a directed acyclic graph called a Free Binary Decision Diagram (FBDD) with N nodes, that quantum state can be prepared by an O(N)-sized quantum circuit. This provides new classes of quantum states that can be prepared efficiently, which is expected to broaden the scope of application of the existing quantum algorithms.
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Achievements of the joint research project with the Fujii Lab of Osaka University)
Quantum computers have the potential of efficiently solving non-linear ordinary differential equations (ODEs), which play a key role in a number of industrial and scientific fields. It still remains one of the major research challenges, however, to clarify that which nonlinear ODEs, and under what assumptions, can achieve exponential speedup using a quantum computer. We have proposed a class of non-linear ODEs called quantum solvable ODEs. Moreover, we have proved that quantum solvable ODEs can be simulated in logarithmical computational resource in the problem size N.
■Co-authored papers with Fujii Lab.
Quantum Solvable Nonlinear Differential Equations
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We look forward to receiving feedback on each of these presentations from experts.