Talk: Controlling and probing spins

Spin transport process in the ferromagnets interfacing with heavy metal with high spin orbit coupling has drawn huge attention in spintronic and photonic community to realize the ultrafast Opto-spintronic devices. Generation and detection of pure spin current is important to achieve high density spin devices functional at terahertz speed. 

In his presentation, firstly, Dr. Rohit Medwal will discuss about material design to achieve large spin to change interconversion efficiency and methods to estimate the spin to charge conversion. The different methods to characterize the spin transport such as spin-pumping - inverse spin Hall effect and spin torque ferromagnetic resonance will be discussed. 

In the second part of the presentation, he will discuss about the importance of the spin to change conversion to generate the terahertz emission which usually happens at ultrafast time scale. Thereafter, He will talk about the basics of the Femto-magnetism and laser field-induced quenching of the ferromagnetic ordering and ultrafast super-diffusion process resulting in the emission of terahertz photons. The phase of emitted terahertz radiation can be controlled by photothermal effect by switching of the direction of terahertz spin current. Such schemes may lead to the realization of a novel class of integrated Opto-spintronics devices.