Tags - (4) single ion quantum validation

Department(s)/lab(s): School of Physics | Melbourne Ion Implantation and Single Ion Group (Jamieson) @ UMelb
Summary:

Jamieson's group built the counted single-ion implantation capability that underpins every donor spin qubit made at UNSW and Melbourne: individual P, Sb or Bi ions are implanted into silicon through a nanoscale aperture while on-chip detector electrodes register the electron-hole pairs from each ion stop event, so the number and position of dopants is known rather than assumed. Recent directions extend this to high-atomic-number donors for nuclear-spin qudits, to colour-centre creation in diamond and silicon carbide by counted implantation, and to characterising the damage and charge environment those ions leave behind. The work is fabrication-forward but its scientific content is single-particle detection metrology. Positioned against the established body of NV-ensemble quantum sensing work β€” DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity β€” his contribution is upstream: the deterministic creation and validation of the very spin defects whose ensembles are later interrogated by DEER and nanoscale NMR at pT/sqrt(Hz).

Department(s)/lab(s): School of Physics | Electronic and Condensed Matter Physics Group (McCallum) @ UMelb
Summary:

McCallum works on the materials and detector physics of donor qubits in silicon and colour centres in diamond and silicon carbide: defect engineering by ion implantation and annealing, characterisation of the resulting spin coherence, and β€” most relevant to a sensing postdoc β€” the development of superconducting and semiconductor detectors capable of registering single implanted ions with near-unit efficiency, which is what turns implantation from a statistical process into a deterministic one. He also works on near-surface colour centres, where surface termination and Fermi-level control set the achievable coherence. Positioned against the established body of NV-ensemble quantum sensing work β€” DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity β€” his group supplies the near-surface, coherence-optimised spin ensembles that DEER, nanoscale NMR and T1-relaxometry protocols at pT/sqrt(Hz) sensitivity actually depend on.

Department(s)/lab(s): Physics & Astronomy – Photon Science Institute | Parkinson Group (Ultrafast Spectroscopy of Photonic Materials) @ Manchester
Summary:

Parkinson's group uses ultrafast optical spectroscopy to study carrier dynamics in photonic materials with quantum device applications. Research directions: (1) Time-resolved photoluminescence β€” TRPL with single-photon counting to map exciton lifetimes, diffusion, and defect trapping in GaN, perovskite, and 2D semiconductor quantum wells; (2) Optical single-particle spectroscopy β€” isolating single nanowires or nanocrystals for defect-free measurements of intrinsic optical properties; (3) Photon-number statistics β€” Hanbury Brown–Twiss measurements of single-photon purity from quantum dots and localized excitons; (4) Semiconductor quantum sensing interfaces β€” studying how carrier dynamics affect the fidelity of semiconductor-based quantum sensors and emitters.

Department(s)/lab(s): School of Physics | Rogge Single Dopant Spectroscopy Group @ UNSW
Summary:

Rogge (formerly Delft) works on the spectroscopy of individual dopant atoms in silicon: using transport, STM and microwave spectroscopy to read out the orbital, valley and spin structure of single donors and acceptors, including their coupling to strain, electric fields and each other. The group has mapped the wavefunctions of individual dopants and used acceptor spin-orbit coupling for electric-field-driven spin control. This is single-quantum-object measurement rather than device engineering. Positioned against the established body of NV-ensemble quantum sensing work β€” DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity β€” single-donor spectroscopy is the silicon analogue of single-NV work: the same questions about coherence, bath engineering and readout fidelity that fix pT/sqrt(Hz) ensemble performance appear here in a platform where the sensor can be placed with atomic precision and interrogated electrically rather than optically.