Coupling between a crystal of di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium radicals and a superconducting microwave resonator is investigated in a circuit quantum electrodynamics (circuit QED) architecture. The crystal exhibits paramagnetic behavior above 4 K, with antiferromagnetic correlations appearing below this temperature, and we demonstrate strong coupling at base temperature. The magnetic resonance acquires a field angle dependence as the crystal is cooled down, indicating anisotropy of the exchange interactions. These results show that multispin modes in organic crystals are suitable for circuit QED, offering a platform for their coherent manipulation. They also utilize the circuit QED architecture as a way to probe spin correlations at low temperature.Coupling between a crystal of di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium radicals and a superconducting microwave resonator is investigated in a circuit quantum electrodynamics (circuit QED) architecture. The crystal exhibits paramagnetic behavior above 4 K, with antiferromagnetic correlations appearing below this temperature, and we demonstrate strong coupling at base temperature. The magnetic resonance acquires a field angle dependence as the crystal is cooled down, indicating anisotropy of the exchange interactions. These results show that multispin modes in organic crystals are suitable for circuit QED, offering a platform for their coherent manipulation. They also utilize the circuit QED architecture as a way to probe spin correlations at low temperature.

arXiv:1703.06202Physical Review LettersOct 2, 201756 citations

Microwave multimode memory with an erbium spin ensemble

S. Probst, Hannes Rotzinger, Alexey Vladimirovich Ustinov +1 more

Hybrid quantum systems combining circuit QED with spin-doped solids are an attractive platform for distributed quantum information processing. There, the magnetic ions serve as coherent memory elements and reversible conversion elements of microwave to optical qubits. Among many possible spin-doped solids, erbium ions offer the unique opportunity for a coherent conversion of microwave photons into the telecom C band at $1.54\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ employed for long distance communication. In our work, we perform a time-resolved electron spin resonance study of an ${\mathrm{Er}}^{3+}:{\mathrm{Y}}_{2}{\mathrm{SiO}}_{5}$ spin ensemble at millidegrees Kelvin temperatures and demonstrate multimode storage and retrieval of up to 16 coherent microwave pulses. The memory efficiency is measured to be ${10}^{\ensuremath{-}4}$ at a coherence time of ${T}_{2}=5.6\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}$. We observe a saturation of the spin coherence time below 50 mK due to full polarization of the surrounding electronic spin bath.Hybrid quantum systems combining circuit QED with spin-doped solids are an attractive platform for distributed quantum information processing. There, the magnetic ions serve as coherent memory elements and reversible conversion elements of microwave to optical qubits. Among many possible spin-doped solids, erbium ions offer the unique opportunity for a coherent conversion of microwave photons into the telecom C band at $1.54\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ employed for long distance communication. In our work, we perform a time-resolved electron spin resonance study of an ${\mathrm{Er}}^{3+}:{\mathrm{Y}}_{2}{\mathrm{SiO}}_{5}$ spin ensemble at millidegrees Kelvin temperatures and demonstrate multimode storage and retrieval of up to 16 coherent microwave pulses. The memory efficiency is measured to be ${10}^{\ensuremath{-}4}$ at a coherence time of ${T}_{2}=5.6\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}$. We observe a saturation of the spin coherence time below 50 mK due to full polarization of the surrounding electronic spin bath.

arXiv:1501.01499Physical Review BJul 23, 201569 citations

Experimental Circuit QED

Patrice Bertet

WORLD SCIENTIFIC eBooksJan 7, 20140 citations

Hybrid Circuit QED with Spin Qubits

Andreas Landig

Jan 1, 20190 citations

Spin Statistics, Magnetic Resonance, Spin Motion and Echoes

Attilio Rigamonti, P. Carretta

UNITEXT for physicsJan 1, 20150 citations

{\mathrm{Er}}^{3+}:{\mathrm{Y}}_{2}{\mathrm{SiO}}_{5}

spin ensemble at millidegrees Kelvin temperatures and demonstrate multimode storage and retrieval of up to 16 coherent microwave pulses. The memory efficiency is measured to be ${10}^{\ensuremath{-}4}$ at a coherence time of ${T}_{2}=5.6\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}$. We observe a saturation of the spin coherence time below 50 mK due to full polarization of the surrounding electronic spin bath.