Making Diamond Qubits Talk to Light

Lachlan J. Rogers, Fedor Jelezko

Senkalla, Katharina

From jewelry stores to quantum labs — diamonds have found a new sparkle in the world of quantum technologies. Their atomic-scale color centers host electron and nuclear spins that can serve as long-lived qubits and bright photon sources, making them powerful candidates for realizing quantum networks. In this talk, I’ll explore how these tiny defects in diamond enable us to connect stationary quantum memories through flying photonic qubits. We’ll look at the fundamental principles, key experimental advances, and ongoing challenges in creating scalable quantum links — and discuss how “shining light on defects” may become the key to the quantum internet.

Anonymous

I. S. Osborne

Physics There are several different approaches to quantum information processing currently under development, including (but not exhaustively) superconducting circuits, nitrogen vacancy defects in diamond, and semiconductor quantum dots. Each one relies on the basic building block of a qubit, a two-level quantum system, on which the information can be stored and manipulated. In the semiconductor quantum dot approach, manipulating the spin of a single electron is promising because it has all the requirements: being fast, controllable and stable. A downside, however, has been the issue of scalability. Any useful quantum processor will require a system of many qubits, but getting quantum dots to talk to each other has presented a challenge. Addressing a preliminary point of this issue, Schaibley et al. show that the light (a single photon) emitted from the excited state of a charged quantum dot is entangled with the spin of the electron on the dot. The authors argue that by making the single photons emitted from other distinct quantum dots interact, it may be possible to then entangle the spins on these quantum dots and thus realize a scalable architecture. Phys. Rev. Lett. 110 , 167401 (2013).

Alp Sipahigil, Michael Goldman, Alexey V. Akimov +6 more

Jörg Wrachtrup

The talk will highlight recent achievements in solid state quantum optics and spin physics with diamond, which may also have important spin off to other areas like e.g. biophysics.