Proposal for a Nanomechanical Qubit

Mechanical oscillators have been demonstrated with very high quality factors over a wide range of frequencies. These also couple to variety fields and forces, making them ideal as sensors. The realization mechanically-based quantum bit could therefore provide an important new platform for computation sensing. Here we show that by coupling one the flexural modes suspended carbon nanotube charge states double dot defined in nanotube, it is possible induce sufficient anharmonicity mechanical oscillator so coupled system can be used bit. This however only achieved when device enters ultrastrong regime. We discuss conditions appear, Hamiltonian mapped onto anharmonic oscillator, allowing us work out energy level structure how decoherence from are inherited qubit. Remarkably, dephasing due expected reduced several orders magnitude system. outline qubit control, readout protocols, CNOT gate two qubits microwave cavity, finally static force sensor.