Hydrogenic spin-valley states of the bromine donor in 2H-MoTe2

In semiconductors, the identification of doping atomic elements allowing to encode a qubit within spin states is of intense interest for quantum technologies. In transition metal dichalcogenides semiconductors, the strong spin-orbit coupling produces locked spin-valley states with expected long coherence time. Here we study the substitutional Bromine Br-Te dopant in 2H-MoTe2. Electron spin resonance measurements show that this dopant carries a spin with long-lived nanoseconds coherence time. Using scanning tunneling spectroscopy, we find that the hydrogenic wavefunctions associated with the dopant levels have characteristics spatial modulations that result from their hybridization to the Q-valleys of the conduction band. From a Fourier analysis of the conductance maps, we find that the amplitude and phase of the Fourier components change with energy according to the different irreducible representations of the impurity-site point-group symmetry. These results demonstrate that a dopant can inherit the locked spin-valley properties of the semiconductor and so exhibit long spin-coherence time. Doping 2D materials is an effective way to engineer a wide range of properties of interest from catalysis to quantum bits. Here, the authors investigate Br-doped 2H-MoTe2 using electron spin resonance and scanning tunneling spectroscopy, demonstrating that the dopant-orbitals hybridise to the Q-valleys of the conduction band and produce long-lived spin states protected by spin-valley locking.

Automated summary

The authors investigated Br-doped 2H-MoTe2 semiconductor using electron spin resonance and scanning tunneling spectroscopy. They found that the dopant orbitals hybridize to the Q-valleys of the conduction band, resulting in long-lived spin states. Doping 2D materials is an effective way to engineer properties of interest such as catalysis and quantum bits.