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In this paper, we show how to construct XX Hamiltonians that realize perfect quantum state transfer and also have the property that the overlap of the time evolved state with the initial state is zero for some time before the transfer time. If the latter takes place, we call it an early exclusion state.We also show that in some cases, early state exclusion is impossible. The proofs rely on properties of Krawtchouk and Chebyshev polynomials.
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This content will become publicly available on July 25, 2026
Optimising Perfect Quantum State Transfer for Timing Insensitivity
When studying the perfect transfer of a quantum state from one site to another, it is typically assumed that one can receive the arriving state at a specific instant in time, with perfect accuracy. Here, we study how sensitive perfect state transfer is to that timing. We design engineered spin chains which reduce their sensitivity, proving that this construction is asymptotically optimal. The same construction is applied to the task of creating superpositions, also known as fractional revival.
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- Award ID(s):
- 2427020
- PAR ID:
- 10634040
- Publisher / Repository:
- arxiv.org (quant-ph)
- Date Published:
- Edition / Version:
- 1
- Subject(s) / Keyword(s):
- Quantum state transfer quantum communication
- Format(s):
- Medium: X Size: 1MB Other: pdf
- Size(s):
- 1MB
- Sponsoring Org:
- National Science Foundation
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