Please use this identifier to cite or link to this item:
|Type:||Artigo de periódico|
|Title:||Nonadditivity of decoherence rates in superconducting qubits|
|Abstract:||We show that the relaxation and decoherence rates T(1)(-1) and T(2)(-1) of a qubit coupled to several noise sources are in general not additive, i.e., that the total rates are not the sums of the rates due to each individual noise source. To demonstrate this, we calculate the relaxation and pure dephasing rates T(1)(-1) and T(phi)(-1) of a superconducting (SC) flux qubit in the Born-Markov approximation in the presence of several circuit impedances Z(i) using network graph theory and determine their deviation from additivity (the mixing term). We find that there is no mixing term in T(phi)(-1) and that the mixing terms in T(1)(-1) and T(2)(-1) can be positive or negative, leading to reduced or enhanced relaxation and decoherence times T(1) and T(2). The mixing term due to the circuit inductance L at the qubit transition frequency omega(01) is generally of second order in omega(01)L/Z(i), but of third order if all impedances Z(i) are pure resistances. We calculate T(1,2) for an example of a SC flux qubit coupled to two impedances.|
|Editor:||Amer Physical Soc|
|Appears in Collections:||Unicamp - Artigos e Outros Documentos|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.