gusucode.com > qit_matlab_0.10.0工具箱源码程序 > qit/+seq/corpse.m
function [s] = corpse(theta, phi) % CORPSE Sequence for fixing off-resonance (\sigma_z bias) errors. % s = corpse(theta [, phi]) % % Returns the CORPSE control sequence s for fixing off-resonance % errors, i.e. ones arising from a constant but unknown % \sigma_z bias in the Hamiltonian. % % The target rotation is \theta_\phi in the NMR notation. % % CORPSE: Compensation for Off-Resonance with a Pulse SEquence %! Cummins et al., "Tackling systematic errors in quantum logic gates with composite rotations", PRA 67, 042308 (2003). % Ville Bergholm 2009 if (nargin < 2) phi = 0; % default is R_x end n = [1 1 0]; % CORPSE %n = [0 1 0]; % short CORPSE temp = asin(sin(theta/2)/2); th1 = 2*pi*n(1) +theta/2 -temp; th2 = 2*pi*n(2) -2*temp; th3 = 2*pi*n(3) +theta/2 -temp; s = seq.nmr([th1, phi; th2, phi+pi; th3, phi]);