Executive Summary : | Femtosecond laser-induced photoexcitation of ferromagnet/heavy metal heterostructures emits broadband terahertz frequencies up to 30 THz. This emission requires an external magnetic field, which poses problems for practical applications. The antiferromagnets (AFM)/ferromagnetic (FM) heterostructure addresses this by offering THz emission without an external field. The mechanism behind this field-free THz emission is the exchange bias field, originating from the exchange coupling of antiferromagnet's and adjacent ferromagnet's magnetization. The research plan aims to fabricate antiferromagnet-based spintronic emitters, design and develop a terahertz emission spectroscopy setup at IIT Kanpur, study magnetization dynamics measurement in AFM, and realize all-optical control of spin currents in AFM. This research will provide an unprecedented understanding of spin dynamics at terahertz frequencies and enable the design of efficient high bandwidth terahertz spintronics emitters with controlled phase and amplitude for advanced material characterization, ultrafast pump-probe spectroscopy, telecommunications, and ultrafast imaging techniques. |