6 papers
Computational entanglement distillation beyond pure states: efficient protocols and fundamental limitations
Takeru Utsumi, Jacopo Rizzo, Ryuji Takagi +1
The information-theoretic approach to entanglement typically relies on arbitrarily many input copies and unboundedly complex operations; however, the available resources are constr…
When Classical Correlations Certify Entanglement Recovery
Takeru Utsumi, Yota Tachibana, Yoshifumi Nakata +4
Entanglement and state distinguishability have long been central topics in quantum foundations. While each has developed into a rich subject in its own right, they can be connected…
Scaling-optimal purification of noisy qubit unitary channels
Ryotaro Niwa, Satoshi Yoshida, Koki Ono +5
We consider the problem of purifying noisy qubit unitary channels. Given the ability to apply an unknown qubit unitary channel followed by depolarizing noise, we aim to construct a…
Random dilation superchannel
Satoshi Yoshida, Ryotaro Niwa, Takeru Utsumi +2
We present a quantum circuit that implements the random dilation superchannel, transforming parallel queries of an unknown quantum channel into the same number of parallel queries…
Quantum algorithms for Uhlmann transformation
Takeru Utsumi, Yoshifumi Nakata, Qisheng Wang +1
Uhlmann's theorem is a central result in quantum information theory, which associates the closeness of two quantum states with that of their purifications. The theorem also well ch…
Explicit decoders using fixed-point amplitude amplification based on QSVT
Takeru Utsumi, Yoshifumi Nakata
Reliably transmitting quantum information via a noisy quantum channel is a central challenge in quantum information science. While constructing a decoder is crucial to this goal, l…