Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum manipulation of a two-level mechanical system   We consider a nonlinearly coupled electromechanical system, and develop a
quantitative theory for two-phonon cooling. In the presence of two-phonon
cooling, the mechanical Hilbert space is effectively reduced to its ground and
first excited states, allowing for quantum operations at the level of
individual phonons and preparing nonclassical mechanical states with negative
Wigner functions. We propose a scheme for performing arbitrary Bloch sphere
rotations, and derive the fidelity in the specific case of a $\pi$-pulse. We
characterise detrimental processes that reduce the coherence in the system, and
demonstrate that our scheme can be implemented in state-of-the-art
electromechanical devices.

18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph