Quantum Information Processing with Nanomechanical Qubits

TL;DR

This paper proposes a method for quantum information processing using nanomechanical resonators as qubits, employing electrostatic tuning and optical coupling to achieve high-fidelity quantum gates.

Contribution

It introduces a novel approach to quantum computing with nanomechanical devices, including methods for single-qubit rotations and entangling gates via optical cavities.

Findings

Gate fidelities exceeding 99% are achievable with realistic parameters.

Qubits are encoded in the lowest energy levels of mechanically resonant devices.

Strong anharmonicity is induced by electrostatic fields to define qubit states.

Abstract

We introduce an approach to quantum information processing where the information is stored in the motional degrees of freedom of nanomechanical devices. The qubits of our approach are formed by the two lowest energy levels of mechanical resonators which are tuned to be strongly anharmonic by suitable electrostatic fields. Single qubit rotations are conducted by radio frequency voltage pulses that are applied to individual resonators. Two qubit entangling gates in turn are implemented via a coupling of two qubits to a common optical resonance of a high finesse cavity. We find that gate fidelities exceeding 99% can be achieved for realistic experimental parameters.