Bismuth selenide is a topological insulator, which means it has a bulk band gap but conducting surface states.

Superconductivity is the phenomenon where a material exhibits zero electrical resistance below a certain temperature.

Helium-3 is an example of a quantum spin liquid, which is a state of matter where the spins of the atoms are disordered but still interact with each other.

Magnetoresistance is the effect where a material exhibits a change in its electrical resistance when exposed to a magnetic field.

A photonic crystal is an example of a metamaterial, which is a material with properties that are not found in nature.

Electrochromism is the phenomenon where a material exhibits a change in its optical properties when exposed to an electric field.

All of the above are examples of topological superconductors, which are superconductors that have a non-trivial topological order.

The magnetocaloric effect is the phenomenon where a material exhibits a change in its magnetic properties when exposed to a temperature change.

Gallium arsenide is an example of a quantum Hall insulator, which is a material that exhibits the quantum Hall effect.

Photoconductivity is the phenomenon where a material exhibits a change in its electrical resistance when exposed to light.

Magnetic random-access memory (MRAM) is an example of a spintronic device, which is a device that utilizes the spin of electrons for information storage and processing.

Magnetostriction is the phenomenon where a material exhibits a change in its magnetic properties when exposed to a mechanical stress.

Bismuth telluride is an example of a thermoelectric material, which is a material that can convert heat into electricity or vice versa.

Piezoresistivity is the phenomenon where a material exhibits a change in its electrical resistance when exposed to a strain.

Bismuth selenide is an example of a topological insulator, which means it has a bulk band gap but conducting surface states.