Realizing Bloch Dynamics in a Low-Cost Electrically Driven Acoustic Two-Level System

TL;DR

This paper demonstrates a low-cost, classical acoustic system that emulates quantum Bloch dynamics, enabling visualization and control of state evolution through programmable external fields, bridging quantum concepts with classical wave physics.

Contribution

It introduces a tunable acoustic two-level system that replicates quantum Bloch dynamics using classical components and external modulation, providing a versatile platform for quantum-inspired physics exploration.

Findings

Achieved full Bloch sphere control in a classical acoustic system.

Demonstrated quantum phenomena analogs like Rabi oscillations and Ramsey interference.

Enabled high-fidelity transient acoustic field shaping.

Abstract

Unlike classical bits that can only occupy one of two discrete states, quantum bits (qubits) can exist in arbitrary coherent superpositions of the ground and excited states. This fundamental distinction grants qubits enhanced capabilities for information storage and processing. The Bloch sphere provides an intuitive and powerful geometric framework for visualizing, characterizing, and controlling the dynamical evolution of a qubit under external driving fields. By mapping the state evolution onto the Bloch sphere, processes such as spin flips and phase accumulation can be vividly represented as trajectories, enabling direct insight into coherent control mechanisms. Here, we implement Bloch dynamics in a classical platform by constructing a tunable acoustic two-level system based on high-quality-factor electro-acoustic coupled cavities. Using programmable spatiotemporal external field modulation, we demonstrate full Bloch sphere control through classical analogs of quantum phenomena, including Rabi oscillations, Floquet dynamics, Ramsey interference, and spin echo sequences. Our results bridge coherent Bloch dynamics with classical wave control, revealing a versatile experimental platform for exploring quantum-inspired physics. Furthermore, the system exhibits exceptional capabilities for precision transient acoustic field shaping, enabled by high-fidelity pulse-driven modulation.