The analogy between acoustic modes in nonlinear metamaterials and quantum computing platforms constituted of correlated twolevel systems opens new frontiers in information science. We use an inductive procedure to demonstrate scalable initialization of and scalable unitary transformations on superpositions of states of multiple correlated logical phibits, classical nonlinear acoustic analog of qubits. A multiple phibit state representation as a complex vector in a highdimensional, exponentially scaling Hilbert space is shown to correspond with the state of logical phibits represented in a lowdimensional linearly scaling physical space of an externally driven acoustic metamaterial. Manipulation of the phibits in the physical space enables the implementation of a nontrivial multiple phibit unitary transformation that scales exponentially. This scalable transformation operates in parallel on the components of the multiple phibit complex state vector, requiring only a single physical action on the metamaterial. This work demonstrates that acoustic metamaterials offer a viable path toward achieving massively parallel information processing capabilities that can challenge current quantum computing paradigms.
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Scalable exponentially complex representations of logical phibit states and experimental demonstration of an operable three phibit gate using an acoustic metastructure
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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 NSFPAR ID:
 10439186
 Date Published:
 Journal Name:
 Applied Physics Letters
 Volume:
 122
 Issue:
 14
 ISSN:
 00036951
 Page Range / eLocation ID:
 141701
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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