Logical phibits are nonlinear acoustic modes analogous to qubits and supported by an externally driven acoustic metastructure. A correspondence is established between the state of three correlated logical phibits represented in a lowdimensional linearly scaling physical space and their state representation as a complex vector in a highdimensional exponentially scaling Hilbert space. We show the experimental implementation of a nontrivial three phibit unitary operation analogous to a quantum circuit. This three phibit gate operates in parallel on the components of the three phibit complex state vector. While this operation would be challenging to perform in one step on a quantum computer, by comparison, ours requires only a single physical action on the metastructure.
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Demonstration of a twobit controlledNOT quantumlike gate using classical acoustic qubitanalogues
Abstract The ControlledNOT (CNOT) gate is the key to unlock the power of quantum computing as it is a fundamental component of a universal set of gates. We demonstrate the operation of a twobit CNOT quantumlike gate using classical qubit acoustic analogues, called herein logical phibits. The logical phibits are supported by an externally driven nonlinear acoustic metamaterial composed of a parallel array of three elastically coupled waveguides. A logical phibit has a twostate degree of freedom associated with the two independent relative phases of the acoustic wave in the three waveguides. A simple physical manipulation involving the detuning of the frequency of one of the external drivers is shown to operate on the complex vectors in the Hilbert space of pairs of logical phibits. This operation achieves a systematic and predictable CNOT gate with unambiguously measurable input and output. The possibility of scaling the approach to more phibits is promising.
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 Award ID(s):
 1640860
 NSFPAR ID:
 10353180
 Date Published:
 Journal Name:
 Scientific Reports
 Volume:
 12
 Issue:
 1
 ISSN:
 20452322
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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