Illustration of two scanning tunneling microscope tips above an atomic lattice. On the left, spin-triplet pairs — paired red arrows held in translucent envelopes — sit on a lattice carrying a blue charge density wave modulation; on the right, the atoms carry stripes of alternating red and blue spins. — STM: An atomic scale probe of Cooper pairs, electrons and spins

STM topography of the quantum material UTe₂, showing the atomic lattice — STM topography of UTe₂

Four charge-density-wave relative-phase maps measured at 0, 5.0, 9.0 and 10.5 tesla, showing topological phase defects — circled in black and white — proliferating as the magnetic field increases. Phase is colour-scaled from -π to π. — Field-driven melting of a charge density wave through topological defect generation

Illustration of a spin-polarized STM tip above an atomic lattice with fluctuating surface spins, and the resulting two-level telegraph signal in the tunneling current — Telegraph noise from fluctuating spin chains

Two-panel figure: an optical micrograph of a MnBi₂Te₄ flake device with 6 and 7 septuple-layer regions outlined, beside an NV magnetometry map of the stray field over the same area, scaled from -150 to 150 microtesla — NV magnetometry of a MnBi₂Te₄ flake

From atomic landscapes to quantum dynamics

One of the longstanding challenges in quantum materials research is to understand how collective quantum phenomena emerge from the interactions of many electrons constrained by symmetry, topology, and the underlying crystal environment. Our group develops and employs high-resolution scanning tunneling microscopy and quantum sensing with color centers in diamond to visualize these states at the atomic and nanoscale at low temperatures.

By combining complementary probes of charge and spin, we aim to uncover the microscopic mechanisms behind unconventional superconductivity, correlated charge and spin orders, and other emergent quantum states. Ultimately, our goal is not only to understand these complex materials, but also to develop new experimental tools for discovering, controlling, and harnessing quantum phenomena.

What we work on

Three threads run through the lab

Each grounded in atomic-resolution imaging rather than bulk measurements alone.

Unconventional superconductivity

Quasiparticle interference and spectroscopic imaging of superconductors like UTe₂ and Fe(Se,Te)/Bi₂Te₃ to probe their pairing symmetry.

Intertwined charge & spin orders

Visualizing charge density waves, spin excitations, and topological defects in correlated materials such as 1T-TaS₂ and GdTe₃.

Topological phenomena

Spin-resolved tunneling and spectroscopy of topological Kondo insulators and antiferromagnets, including their surface states and response to external fields.

Recent work

Quasiparticle interference map of the triplet superconductor UTe₂

2026

Quasiparticle interference in triplet superconductor UTe₂

Axionic tunneling signature in a topological Kondo insulator

2025

Axionic tunneling from a topological Kondo insulator

Paired topological defects in the melting charge density wave of UTe₂

2024

Melting the charge density wave in UTe₂ via paired topological defects

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Interested in joining the lab?

We are building a dynamic and inclusive research group at NUS, and we are looking for curious, collaborative and motivated people. If you are interested in condensed matter physics, quantum materials and sensing, we would love to hear from you — please reach out to Prof. Aishwarya!

Get in touch