Coherent properties of single rare-earth spin qubits

Abstract

Rare-earth-doped crystals are excellent hardware for quantum storage of photons. Additional functionality of these materials is added by their waveguiding properties allowing for on-chip photonic networks. However, detection and coherent properties of rare-earth single-spin qubits have not been demonstrated so far. Here we present experimental results on high-fidelity optical initialization, effcient coherent manipulation and optical readout of a single-electron spin of Ce 3 þ ion in a yttrium aluminium garnet crystal. Under dynamic decoupling, spin coherence lifetime reaches T 2 ¼ 2 ms and is almost limited by the measured spin-lattice relaxation time T 1 ¼ 4.5 ms. Strong hyperfine coupling to aluminium nuclear spins suggests that cerium electron spins can be exploited as an interface between photons and long-lived nuclear spin memory. Combined with high brightness of Ce 3 þ emission and a possibility of creating photonic circuits out of the host material, this makes cerium spins an interesting option for integrated quantum photonics.

Engineering near-infrared single-photon emitters with optically active spins in ultrapure silicon carbide

“…For many of these applications it is necessary to have control over single emitters with long spin coherence times. Such single quantum systems have been realized using quantum dots 6 , colour centres in diamond 7 , dopants in nanostructures 8 and molecules 9 . More recently, ensemble emitters with spin dephasing times in the order of microseconds and room-temperature optically detectable magnetic resonance (ODMR) have been identified in silicon carbide (SiC) [10][11][12] , a compound being highly compatible to up-to-date semiconductor device technology.…”

Nondestructive photon detection using a single rare-earth ion coupled to a photonic cavity

“…In order to have a single ion coupled to the photonic cavity, the ion density can be lowered until only a single ion couples to the cavity, but then the single ion may not be near the peak of the cavity mode and also may not have the right frequency. There has also been work on using an ion beam to implant a single REI into a pure crystal with cerium ions implanted in YAG [31] and erbium ions implanted in YSO [32], which currently makes small spots of thousands of REIs but could be scaled down to implanting a single REI.…”

The Gd–Ce Cross-Relaxation Effects in ODMR via Ce3+ Emission in Garnet Crystals

“…They are also widely used in white LEDs [4] and considered as a promising material for quantum storage of optical information [5,6].…”