Zeno and anti-Zeno polarization control of spin-ensembles by induced dephasing

GONZALO A. ÁLVAREZ; D. D. BHAKTAVATSALA RAO; LUCIO FRYDMAN; GERSHON KURIZKI

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Lugar: New York; Año: 2010 vol. 105 p. 160401 - 160401

0031-9007

We experimentally and theoretically demonstrate the purity (polarization) control of qubits entangled with multiple spins, using induced dephasing in nuclear magnetic resonance setups to simulate repeated quantum measurements. We show that one may steer the qubit ensemble towards a quasiequilibrium state of a certain purity by choosing suitable time intervals between dephasing operations. These results demonstrate that repeated dephasing at intervals associated with the anti-Zeno regime leads to ensemble purification, whereas those associated with the Zeno regime lead to ensemble mixing.