Gold dithiolene radical holds a 21 μs spin qubit
Neutral [Au(adt)2] stores the unpaired electron on the ligand, giving phase-memory times up to 21 μs in low-spin solvents and 1.44 μs when doped into a nickel molecular semiconductor.
Source
Enabling single qubit addressability in a molecular semiconductor comprising gold-supported organic radicals
Study at a glance
- Design
- Other — EPR spin-relaxation of [Au(adt)2]−/0 diluted in glassy solvents and isoelectronic Ni matrix
- N
- Molecular spin-qubit materials study — no sample N
- Population
- Gold dithiolene radical complexes in frozen solutions and Ni dilution solids
- Outcome
- Phase-memory times enabling single-qubit addressability
Structured fields used in claim comparison tables when every cited study has a complete layer.
What they did
Authors prepared [Au(adt)2]−/0, assigned Au(III) ligand-radical character by XRD/EPR, measured T1 and TM from 5–80 K in CS2/CCl4-type solvents, and diluted the S=1/2 molecule in isoelectronic [Ni(adt)2].
What they found
TM reaches 21 μs in 4:1 CS2/CCl4 and 15.6–17.6 μs at 10 K in other glasses. Solid Ni dilution shortens TM to 1.44 μs at 10 K via faster T1 in the semiconductor. Hyperfine is tiny versus Au quadrupole because 5d admixture is small.
The limits
What it doesn't show
SOC still kills coherence above ~80 K; room-temperature addressable qubits are not demonstrated.
Key terms
- Phase memory time TM
- How long the electron-spin superposition stays coherent.
- T1
- Spin–lattice relaxation time.
- Ligand radical
- Unpaired electron on the dithiolene, not on Au 5d.
- adt
- Bis(p-anisyl)-1,2-ethenedithiolate ligand.
- SOC
- Spin–orbit coupling from Au that accelerates Raman relaxation above 20 K.
Flashcards
Research intelligence for this paper
See its role on concept claims, tensions it is part of, placement history, and related discoveries.
Quiz yourself
The unpaired electron in [Au(adt)2] is:
Common questions
Where is the unpaired spin?
On the ligand; Au is +III.
Best TM?
21 μs in 4:1 CS2/CCl4.
TM in the Ni host at 10 K?
1.44 μs.
Why low-γ solvents?
Weaker nuclear magnetic moments slow decoherence.
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