Quantum guidelines for solid-state spin defects

Abstract

Defects with associated electron and nuclear spins in solid-state materials have a long history relevant to quantum information science going back to the first spin echo experiments with silicon dopants in the 1950s. Since the turn of the century, the field has rapidly spread to a vast array of defects and host crystals applicable to quantum communication, sensing, and computing. From simple spin resonance to longdistance remote entanglement, the complexity of working with spin defects is fast advancing, and requires an in-depth understanding of their spin, optical, charge, and material properties in this modern context. This is especially critical for discovering new relevant systems dedicated to specific quantum applications. In this review, we therefore expand upon all the key components with an emphasis on the properties of defects and the host material, on engineering opportunities and other pathways for improvement. Finally, this review aims to be as defect and material agnostic as possible, with some emphasis on optical emitters, providing a broad guideline for the field of solid-state spin defects for quantum information.

Manipulating Single‐Photon Emission from Point Defects in Diamond and Silicon Carbide

“…A proposed application area for strain modification of defect qubits is within quantum information processing (see, e.g., ref. [6]), to for instance coherently couple color centers, [195] reduce spectral diffusion, [196,197] and encode information in isolated defect centers by energy tuning. [195] The coupling between spin and strain has been established theoretically for both NV − in diamond [198] and divacancies in SiC.…”

Carbon defect qubit in two-dimensional WS2

“…Point defects with spins in solids which constitute a two-level system are considered as essential building blocks for application in quantum information, computing and sensing 1 – 4 when the electron spin can be initialized and read out with sufficiently long coherence time. The nitrogen-vacancy (NV) centre in diamond has been already identified as a qubit 5 – 8 that can be exploited in diverse quantum technology applications 1 – 4 , 9 . The NV qubit state is initialised and read out by optical means in which spin-photon interface can be realized for quantum communication in the visible wavelength region 10 .…”

Electron-spin interaction in the spin-Peierls phase of the organic spin chain ( o -DMTTF) 2X ( X =Cl, Br, I)

“…2(c)), one spin remains unpaired and the ground state is magnetic, separated from the next states by a gap comparable to that of the infinite chain. However, contrary to a magnetic impurity inside a non-magnetic medium [35], the unpaired spin is correlated to the rest of the chain and the local polarization is spread over many neighbor spins, form- ing a magnetic soliton (as calculated by DMRG [34] with δ=0.1 Fig. 2(d)).…”