Publications by authors named "Markus Grassl"
Article Synopsis
- Quantum error correction is crucial for reliable quantum computing, but it's challenging to implement due to the need for high-quality qubits and gates.
- The authors propose a straightforward error-correcting code that only requires two qubits to address issues from detected amplitude damping in quantum channels.
- They demonstrate the code on different platforms like the IBM Q System and nuclear magnetic resonance, showing that error correction is beneficial when the damping rate surpasses a certain level.
Discrete structures in Hilbert space play a crucial role in finding optimal schemes for quantum measurements. We solve the problem of whether a complete set of five isoentangled mutually unbiased bases exists in dimension four, providing an explicit analytical construction. The reduced density matrices of these 20 pure states forming this generalized quantum measurement form a regular dodecahedron inscribed in a sphere of radius sqrt[3/20] located inside the Bloch ball of radius 1/2.
View Article and Find Full Text PDFWhen quantum states are used to send classical information, the receiver performs a measurement on the signal states. The amount of information extracted is often not optimal due to the receiver's measurement scheme and experimental apparatus. For quantum nondemolition measurements, there is potentially some residual information in the postmeasurement state, while part of the information has been extracted and the rest is destroyed.
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