  We propose a novel symmetrization procedure to beat decoherence for
oscillator-assisted quantum gate operations. The enacted symmetry is related to
the global geometric features of qubits transformation based on ancillary
oscillator modes, e.g. phonons in an ion-trap system. It is shown that the
devised multi-circuit symmetrized evolution endows the system with a two-fold
resilience against decoherence: insensitivity to thermal fluctuations and
quantum dissipation.
