Tags - (18) quantum materials

Department(s)/lab(s): Institute of Physics (KOMET) | AG Klaeui - Nanomagnetism and Spintronics @ JGU
Summary:

Klaeui runs one of Europe's larger nanomagnetism/spintronics groups, working on magnetic skyrmions, antiferromagnetic and ferrimagnetic spin textures, domain-wall dynamics, spin caloritronics and magnon transport, with an eye to low-power memory and unconventional (neuromorphic/stochastic) computing. The connection to this search is the metrology: reading out antiferromagnetic and skyrmionic textures requires stray-field imaging at nanometre scale, and the group uses NV scanning-probe and widefield NV magnetometry alongside synchrotron X-PEEM/XMCD and Kerr microscopy. Relative to the established NV-ensemble quantum-sensing playbook (DEER, nanoscale NMR, T1 relaxometry at pT/sqrt(Hz) ensemble sensitivity), this is a strong 'sensor-as-tool' host -- the NV magnetometer is the instrument, and the physics questions are in the material. Preferred-attribute note: cutting-edge spatial resolution rather than device fabrication is the emphasis on the imaging side, though the group does substantial thin-film growth and lithography.

Department(s)/lab(s): Chemistry / PME | Park Group (Jiwoong) @ UChicago
Summary:

Studies atomically thin 2D quantum materials and their sensing applications. Directions: (1) tr-ARPES and ultrafast spectroscopy of non-equilibrium electronic dynamics in TMDs and graphene heterostructures; (2) 2D material nanophotonic devices for light sensing and emission; (3) wafer-scale CVD growth of hBN, MoS2, WSe2 for integrated quantum devices; (4) scanning probe characterization of local optical and electronic properties. Key tool: time-resolved photoemission as ultrafast electronic structure sensing.

Department(s)/lab(s): School of Physics | Rahman Atomistic Quantum Device Modelling Group @ UNSW
Summary:

Rahman does large-scale atomistic modelling of semiconductor quantum devices: tight-binding and DFT calculations of donor and quantum-dot wavefunctions, valley physics, spin-orbit coupling, hyperfine interactions and the response of all of these to strain and electric field, at system sizes large enough to represent a real device. The group works hand-in-glove with the Morello, Dzurak, Simmons and Rogge experiments, and increasingly uses machine learning to invert measurements into structural information. Positioned against the established body of NV-ensemble quantum sensing work — DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity — the same first-principles machinery is what predicts the hyperfine and spin-bath environment that determines T2 — and therefore the achievable pT/sqrt(Hz) sensitivity — of any solid-state spin sensor, including NV. Computational PI; would suit a candidate wanting a theory/experiment bridge role.

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 — DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity — 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.

Department(s)/lab(s): Materials Science and Engineering | M. Scott Electron Microscopy Lab @ UCB
Summary:

Scott uses and develops 4D-STEM (scanning nanobeam electron diffraction) and other advanced electron-microscopy modalities, including energy-filtered techniques, to map short-range structural order and local diffraction signatures in quantum and semiconductor materials at the nanoscale.

Department(s)/lab(s): School of Physics | Atomic Fabrication Facility (Simmons) @ UNSW
Summary:

Simmons pioneered atomic-precision fabrication in silicon: hydrogen-resist STM lithography, phosphine dosing and epitaxial silicon overgrowth to place individual dopant atoms with sub-nanometre accuracy, then measure them at millikelvin. The programme has produced single-atom transistors, precision dopant arrays used as analogue quantum simulators, and the largest atom-scale device platform in the world; she also founded Silicon Quantum Computing Pty Ltd. The sensing-relevant capability is the single-electron transistor as an exquisitely sensitive electrometer, capable of resolving individual charge transitions and mapping local electrostatic potential at the atomic scale. Positioned against the established body of NV-ensemble quantum sensing work — DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity — her SET electrometry is the charge-domain counterpart to magnetic NV sensing at pT/sqrt(Hz): both are single-quantum-object detectors whose performance is limited by back-action and by the noise of the readout chain. Very large group, strongly fabrication-oriented and commercially entangled, which cuts against the stated preference for sensitivity-limited rather than fabrication-limited work.

Department(s)/lab(s): Physics | Yacoby Lab @ Harvard
Summary:

Yacoby's lab develops scanning-probe quantum sensors, most notably scanning single-NV-center magnetometers and SQUID-on-tip probes, to image nanoscale magnetic textures and current flow in quantum materials at cryogenic and millikelvin temperatures. This scanning-probe approach extends the sensitivity and spatial resolution of NV ensemble quantum sensing experiments (DEER, nanoscale NMR, T1 relaxometry), which established pT/√Hz-class magnetometry, down to single-spin, nanometer-scale imaging of individual quantum materials.

Department(s)/lab(s): PME | Yang Group (Shuolong) @ UChicago
Summary:

Uses MBE thin-film growth combined with equilibrium and non-equilibrium ARPES to sense electronic structure at material interfaces. Directions: (1) non-equilibrium photoemission (tr-ARPES) to map ultrafast electron dynamics in topological and superconducting materials; (2) MBE engineering of interfacial superconductivity and topological orders at oxide and chalcogenide interfaces; (3) light-induced phase transitions probed by ultrafast ARPES as a sensing modality for correlated electron dynamics.