Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coherent manipulation of Andreev states in superconducting atomic
  contacts   Coherent control of quantum states has been demonstrated in a variety of
superconducting devices. In all these devices, the variables that are
manipulated are collective electromagnetic degrees of freedom: charge,
superconducting phase, or flux. Here, we demonstrate the coherent manipulation
of a quantum system based on Andreev bound states, which are microscopic
quasiparticle states inherent to superconducting weak links. Using a circuit
quantum electrodynamics setup we perform single-shot readout of this "Andreev
qubit". We determine its excited state lifetime and coherence time to be in the
microsecond range. Quantum jumps and parity switchings are observed in
continuous measurements. In addition to possible quantum information
applications, such Andreev qubits are a testbed for the physics of single
elementary excitations in superconductors.

17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas