# Arbitrarily accurate twin composite $\pi$ pulse sequences. (arXiv:1802.00958v1 [quant-ph])

The composite phases are given by analytic formulas (rational fractions of

$\pi$) valid for any number of constituent pulses. The transition probability

is expressed by simple analytic formulas and the order of pulse area error

compensation grows linearly with the number of pulses. Therefore, any desired

compensation order can be produced by an appropriate composite sequence; in

this sense, they are arbitrarily accurate. These composite pulses perform

equally well or better than previously published ones. Moreover, the current

sequences are more flexible as they allow total pulse areas of arbitrary

integer multiples of $\pi$.