Scaling of Dynamical Decoupling for Spin Qubits

TY - JOUR

T1 - Scaling of Dynamical Decoupling for Spin Qubits

AU - Medford, J.

AU - Cywinski, L.

AU - Barthel, C.

AU - Marcus, Charles M.

AU - Hanson, M.P.

PY - 2012/2/23

Y1 - 2012/2/23

N2 - We investigate the scaling of coherence time T 2 with the number of π pulses n π in a singlet-triplet spin qubit using Carr-Purcell-Meiboom-Gill (CPMG) and concatenated dynamical decoupling (CDD) pulse sequences. For an even numbers of CPMG pulses, we find a power law T 2(n π)γ e, with γ e=0. 72±0.01, essentially independent of the envelope function used to extract T 2. From this surprisingly robust value, a power-law model of the noise spectrum of the environment, S(ω)∼ω -β, yields β=γ e/(1-γ e)=2.6±0.1. Model values for T 2n π using β=2.6 for CPMG with both even and odd n π up to 32 and CDD orders 3 through 6 compare very well with the experiment.

AB - We investigate the scaling of coherence time T 2 with the number of π pulses n π in a singlet-triplet spin qubit using Carr-Purcell-Meiboom-Gill (CPMG) and concatenated dynamical decoupling (CDD) pulse sequences. For an even numbers of CPMG pulses, we find a power law T 2(n π)γ e, with γ e=0. 72±0.01, essentially independent of the envelope function used to extract T 2. From this surprisingly robust value, a power-law model of the noise spectrum of the environment, S(ω)∼ω -β, yields β=γ e/(1-γ e)=2.6±0.1. Model values for T 2n π using β=2.6 for CPMG with both even and odd n π up to 32 and CDD orders 3 through 6 compare very well with the experiment.

U2 - 10.1103/PhysRevLett.108.086802

DO - 10.1103/PhysRevLett.108.086802

M3 - Journal article

C2 - 22463554

SN - 0031-9007

VL - 108

SP - 086802

JO - Physical Review Letters

JF - Physical Review Letters

IS - 8

ER -