electronics and photonics
Quantum-transport modelling of nanoscale electronic, thermoelectric and optoelectronic devices.
Research directions
Topological-insulator FETs
Gate-field-driven quantum spin Hall to trivial transitions in 1T′-MoS₂, 1T′-WTe₂, stanene and Bi₄X₄ (X = Br, I) nanoribbons, and how helical edge conduction and Kramers protection behave under disorder and realistic gate stacks.
2D-material transistors
Borophene, black phosphorus (gate-all-around nanosheets), graphene nanoribbons, graphynes, bismuthene and MoSe₂ nanoribbons. We look at electric-field-induced gap engineering and short-channel limits.
Metal contacts to 2D semiconductors
Fermi-level pinning at metallic NbₓW₁₋ₓSe₂/WSe₂ van der Waals contacts: first-principles (PBE+SOC+D3) band alignment, metal-induced gap states and the charge-neutrality level, showing that the small hole barrier comes from valence-side pinning and persists under Nb/W alloying. With Ahnaf Rashid Olee.
Thermoelectric materials
Pressure- and strain-engineered Bi₂Te₃ and related topological thermoelectrics, using DFT + spin-orbit coupling and Boltzmann transport (BoltzTraP2).
Materials research
First-principles screening and design of 2D, topological and thermoelectric materials: band structure, spin–orbit coupling, Wannier interpolation and topology (Z₂, nodal lines), with attention to contacts, dielectrics and stability.
TCAD simulations
Device-level simulation in Sentaurus and Silvaco: 3D electrostatics, short-channel and gate-all-around structures, drift-diffusion and hydrodynamic models, calibrated against measurements and atomistic results.
Ferroelectric FET (FeFET) memory
Ferroelectric-gate transistors for non-volatile memory and in-memory computing: polarization switching, retention and endurance, multi-gate and dendritic FeFETs, simulated across TCAD and SPICE.
SOT memory
Spin–orbit-torque magnetic memory: topological-insulator and heavy-metal spin sources, spin textures in Bi₂Se₃-type nanoribbons, and switching efficiency and energy of SOT devices.
Predictive coding
Predictive-coding networks mapped onto device-aware hardware, so that learning rules run on FeFET and other emerging devices with their real non-idealities.
Complementary FET (CFET)
Vertically stacked n- and p-type channels for continued scaling below the nanosheet node: electrostatics, parasitics and variability, studied with TCAD and compact models.
Photonic biosensors
Photonic-crystal-fibre surface-plasmon-resonance (PCF-SPR) sensors with molecularly imprinted polymer (MIP) sensing layers, designed for selective detection of pathogens such as faecal streptococci in drinking water.
Coherent electron–photon interaction
Phase-coherent optoelectronics in graphene nanostructures: quantum-interference photodetectors, wavelength-dependent photocurrent switching and nanoscale spectrometers (from my PhD at Georgia Tech).
Methods and tools
| Layer | Tools |
|---|---|
| Electronic structure | Quantum ESPRESSO (PBE, HSE06, SOC, DFT-D3), Wannier90, WannierTools, Z2Pack |
| Quantum transport | Custom NEGF codes (MATLAB, Python), Landauer–Büttiker, self-consistent Schrödinger–Poisson, phonon dephasing |
| Device / TCAD | Synopsys Sentaurus, Silvaco ATLAS, SPICE, 3D electrostatics |
| Transport theory | BoltzTraP2, drift-diffusion, hydrodynamic and Monte-Carlo comparisons |