Topological insulators

Illustration from D. Hsieh et al., Nature 460, 1101 (2009).

3D Topological materials (Bi2Se3, Bi2Te3 etc.) are the recent addition to the recently discovered class of topologically non-trivial materials.

Coexistence of metal-like surface states along with insulating bulk states are the special features of these kind of materials.

As these surface states are helical and protected from back-scattering by time-reversal symmetry, they provide the unique framework to study interesting physics (for example possible realization of Majorana fermions by hybridizing with superconductivity) and also provide the opportunity to explore the scope of technological application (Spintronics, low power electronics etc).

Ongoing Research

• Quantum transport properties of three dimensional topological insulators
• Field effect transistor with topological insulators: Towards Dirac physics at room temperature
• Electrical noise in topological insulator-based field effect devices
• Magnetism and time reversal symmetry at the topological insulator surfaces

Research Outline

Quantum transport and noise in 3D topological insulators

Although the existence of non-trivial topological states are shown successfully by Angle Resolved Photo-emission Spectroscopy (ARPES), intrinsically doped bulk bands make it challenging to access the surface transport by electrical transport measurement. It is important to understand the nature and dynamics of disorder in these systems to successfully utilize the surface states to its’ full potential. Our current work in this field involves measuring the quantum transport and flicker noise in topological insulators, which are expected to provide crucial information on the disorder kinetic, surface surface transport and other related effects.

More soon…