Electrically Tunable Terahertz Resonance in Antiferromagnetic NiO/Pt Heterostructures

Antiferromagnets that facilitate terahertz (THz) spin resonances have the potential to revolutionize highspeed electronics at the nanoscale. The electrical control of THz spin resonances is the key to such THz devices; however, experimental demonstration has remained elusive. In this work, we demonstrate electrically tunable THz spin resonance in an antiferromagnetic NiO/Pt heterostructure by employing both low-wavenumber Raman and continuous-wave THz spectroscopy techniques. A redshift of over 100 GHz in the NiO spin resonance frequency of around 1 THz is observed by applying charge currents along the adjacent Pt layer. A control experiment with NiO/Cu and temperature-dependent measurement confirm that the dominant tuning mechanism is Joule heating. Finally, a prototype device is designed to achieve an electrical control of THz transmission at dual channels of 0.96 and 1 THz, leading to a Q factor of 56. This work opens up the possibility for the implementation of tunable THz devices utilizing antiferromagnetic spin resonance.