Ultralong spin coherence time in isotopically engineered diamond.
As quantum mechanics ventures into the world of applications and engineering, materials science faces the necessity to design matter to quantum grade purity. For such materials, quantum effects define their physical behaviour and open completely new (quantum) perspectives for applications. Carbon-based materials are particularly good examples, highlighted by the fascinating quantum properties of, for example, nanotubes or graphene. Here, we demonstrate the synthesis and application of ultrapure isotopically controlled single-crystal chemical vapour deposition (CVD) diamond with a remarkably low concentration of paramagnetic impurities. The content of nuclear spins associated with the (13)C isotope was depleted to 0.3% and the concentration of other paramagnetic defects was measured to be <10(13) cm(-3). Being placed in such a spin-free lattice, single electron spins show the longest room-temperature spin dephasing times ever observed in solid-state systems (T2=1.8 ms). This benchmark will potentially allow observation of coherent coupling between spins separated by a few tens of nanometres, making it a versatile material for room-temperature quantum information processing devices. We also show that single electron spins in the same isotopically engineered CVD diamond can be used to detect external magnetic fields with a sensitivity reaching 4 nT Hz(-1/2) and subnanometre spatial resolution.
Balasubramanian
Gopalakrishnan
G
Physikalisches Institut, Universität Stuttgart, 70550 Stuttgart, Germany.
Neumann
Philipp
P
Twitchen
Daniel
D
Markham
Matthew
M
Kolesov
Roman
R
Mizuochi
Norikazu
N
Isoya
Junichi
J
Achard
Jocelyn
J
Beck
Johannes
J
Tissler
Julia
J
Jacques
Vincent
V
Hemmer
Philip R
PR
Jelezko
Fedor
F
Wrachtrup
Jörg
J
D002247:Carbon Isotopes; D002616:Chemical Engineering / Q000379:methods*; D018130:Diamond / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry; D011789:Quantum Theory
D002247:Carbon Isotopes; D018130:Diamond; D009584:Nitrogen