33 citations · 97 across the 5 of their papers we have counts for
5 papers
Gate fidelity of arbitrary single-qubit gates constrained by conservation laws
Tokishiro Karasawa, Julio Gea-Banacloche, Masanao Ozawa
Recent investigations show that conservation laws limit the accuracy of gate operations in quantum computing. The inevitable error under the angular momentum conservation law has b…
Channel Estimation Theory of Low-Noise Multiple Parameters:Attainablity Problem of the Cram{é}r-Rao Bounds
Masahiro Hotta, Tokishiro Karasawa
For decoherence processes induced by weak interactions with the environment, a general quantum channel with one noise parameter has been formulated. This channel is called low-nois…
Conservation-Law-Induced Quantum Limits for Physical Realizations of the Quantum NOT Gate
Tokishiro Karasawa, Masanao Ozawa
In recent investigations, it has been found that conservation laws generally lead to precision limits on quantum computing. Lower bounds of the error probability have been obtained…
N-body-extended Channel Estimation for Low-Noise Parameters
M. Hotta, T. Karasawa, M. Ozawa
The notion of low-noise channels was recently proposed and analyzed in detail in order to describe noise-processes driven by environment [M. Hotta, T. Karasawa and M. Ozawa, Phys.…
Ancilla-Assisted Enhancement of Channel Estimation for Low-Noise Parameters
Masahiro Hotta, Tokishiro Karasawa, Masanao Ozawa
In order to make a unified treatment for estimation problems of a very small noise or a very weak signal in a quantum process, we introduce the notion of a low-noise quantum channe…