Logical phi-bits 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 phi-bits represented in a low-dimensional linearly scaling physical space and their state representation as a complex vector in a high-dimensional exponentially scaling Hilbert space. We show the experimental implementation of a nontrivial three phi-bit unitary operation analogous to a quantum circuit. This three phi-bit gate operates in parallel on the components of the three phi-bit 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 phi-bits, classical analogues of qubits using nonlinear acoustic waves, supported by an externally driven acoustic metastructure. These phi-bits bridge a low-dimensional linearly scaling physical space to a high-dimensional 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 three-phi-bit unitary operation analogous to a quantum circuit but achieved via a single action on the metastructure, whereby the qubit-based equivalent requires sequences of qubit gates. A phi-bit-based 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 quantum-analogous manners, blending the best of both domains.
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- NSF-PAR ID:
- 10520153
- Publisher / Repository:
- The American Institute of Physics, publisher, Bulletin of the American Physical Society
- Date Published:
- ISSN:
- 0003-0503
- Format(s):
- Medium: X Other: pdf
- Location:
- Minneapolis, MN
- Sponsoring Org:
- National Science Foundation
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