Repetitive readout of a single electronic spin via quantum logic with nuclear spin ancillae.
Robust measurement of single quantum bits plays a key role in the realization of quantum computation and communication as well as in quantum metrology and sensing. We have implemented a method for the improved readout of single electronic spin qubits in solid-state systems. The method makes use of quantum logic operations on a system consisting of a single electronic spin and several proximal nuclear spin ancillae in order to repetitively readout the state of the electronic spin. Using coherent manipulation of a single nitrogen vacancy center in room-temperature diamond, full quantum control of an electronic-nuclear system consisting of up to three spins was achieved. We took advantage of a single nuclear-spin memory in order to obtain a 10-fold enhancement in the signal amplitude of the electronic spin readout. We also present a two-level, concatenated procedure to improve the readout by use of a pair of nuclear spin ancillae, an important step toward the realization of robust quantum information processors using electronic- and nuclear-spin qubits. Our technique can be used to improve the sensitivity and speed of spin-based nanoscale diamond magnetometers.
Jiang
L
L
Department of Physics, Harvard University, Cambridge, MA 02138, USA.
Hodges
J S
JS
Maze
J R
JR
Maurer
P
P
Taylor
J M
JM
Cory
D G
DG
Hemmer
P R
PR
Walsworth
R L
RL
Yacoby
A
A
Zibrov
A S
AS
Lukin
M D
MD