QUANTUM LIMIT OF MEASUREMENT AND THE PROJECTION POSTULATE
QUANTUM LIMIT OF MEASUREMENT AND THE PROJECTION POSTULATE
We study an electrostatic qubit monitored by a point-contact detector. Projecting an entire qubit-detector wave function on the detector eigenstates we determine the precision limit for the qubit measurements, allowed by quantum mechanics. We found that this quantity is determined by qubit dynamics as well as decoherence, generated by the …