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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This content will become publicly available on March 4, 2025
Revolutionizing Computations: Quantum Circuit Analogues with Nonlinear Acoustic Waves
Quantum computing utilizes superposition and entanglement to surpass classical computer capabilities. Central to this are qubits and their use to realize parallel quantum algorithms through circuits of simple one or two qubit gates. Controlling and measuring quantum systems is challenging. Here, we introduce a paradigm utilizing logical phibits, classical analogues of qubits using nonlinear acoustic waves, supported by an externally driven acoustic metastructure. These phibits bridge a lowdimensional linearly scaling physical space to a highdimensional exponentially scaling Hilbert space in which parallel processing of information can be realized in the form of unitary operations. Here, we show the implementation of a nontrivial threephibit unitary operation analogous to a quantum circuit but achieved via a single action on the metastructure, whereby the qubitbased equivalent requires sequences of qubit gates. A phibitbased approach might offer advantages over quantum systems, especially in tasks requiring large complex unitary operations. This breakthrough hints at a fascinating intersection of classical and quantum worlds, potentially redefining computational paradigms by harnessing nonlinear classical mechanical systems in quantumanalogous manners, blending the best of both domains.
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 NSFPAR ID:
 10520153
 Publisher / Repository:
 The American Institute of Physics, publisher, Bulletin of the American Physical Society
 Date Published:
 ISSN:
 00030503
 Format(s):
 Medium: X Other: pdf
 Location:
 Minneapolis, MN
 Sponsoring Org:
 National Science Foundation
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