Scandium-doped aluminum nitride(AlScN)with an asymmetric hexagonal wurtzite structure exhibits enhanced second-order nonlinear and piezoelectric properties compared to aluminum nitride(AlN),while maintaining a relativ...Scandium-doped aluminum nitride(AlScN)with an asymmetric hexagonal wurtzite structure exhibits enhanced second-order nonlinear and piezoelectric properties compared to aluminum nitride(AlN),while maintaining a relatively large bandgap.It provides a promising platform for photonic circuits and facilitates the seamless integration of passive and active functional devices.Here,we present the design,fabrication,and characterization of Al_(0.904)Sc_(0.096)N electro-optic(EO)micro-ring modulators,introducing active functionalities to the chip-scale AlScN platform.These waveguide-integrated EO modulators utilize sputtered Al_(0.904)Sc_(0.096)N thin films as the light-guiding medium,with the entire fabrication process being compatible with complementary metaloxide-semiconductor(CMOS)technology.We extract the in-device effective EO coefficient of 2.86 pm/V at12 GHz.The devices show a minimum half-wave voltage-length product of 3.12 V·cm at a modulation frequency of 14 GHz,and achieve a 3-dB modulation bandwidth of approximately 22 GHz.Our work provides a promising modulation scheme for cost-effective silicon-integrated photonics systems.展开更多
Optical control of magnons in two-dimensional(2D)materials promises new functionalities for spintronics and magnonics in atomically thin devices.Here,we report control of magnon dynamics,using laser polarization,in a ...Optical control of magnons in two-dimensional(2D)materials promises new functionalities for spintronics and magnonics in atomically thin devices.Here,we report control of magnon dynamics,using laser polarization,in a ferromagnetic van der Waals(vdW)material,Fe3.6Co1.4GeTe2.The magnon amplitude,frequency,and lifetime are controlled and monitored by time-resolved pump-probe spectroscopy.We show substantial(over 25%)and continuous modulation of magnon dynamics as a function of incident laser polarization.Our results suggest that the modification of the effective demagnetization field and magnetic anisotropy by the pump laser pulses with different polarizations is due to anisotropic optical absorption.This implies that pump laser pulses modify the local spin environment,which enables the launch of magnons with tunable dynamics.Our first-principles calculations confirm the anisotropic optical absorption of different crystal orientations.Our findings suggest a new route for the development of opto-spintronic or opto-magnonic devices.展开更多
基金National Natural Science Foundation of China(U23A20356,62205193,62204149)Shanghai Collaborative Innovation Center of Intelligent Sensing Chip TechnologyNatural Science Foundation of Shanghai Municipality(23ZR1442400)。
文摘Scandium-doped aluminum nitride(AlScN)with an asymmetric hexagonal wurtzite structure exhibits enhanced second-order nonlinear and piezoelectric properties compared to aluminum nitride(AlN),while maintaining a relatively large bandgap.It provides a promising platform for photonic circuits and facilitates the seamless integration of passive and active functional devices.Here,we present the design,fabrication,and characterization of Al_(0.904)Sc_(0.096)N electro-optic(EO)micro-ring modulators,introducing active functionalities to the chip-scale AlScN platform.These waveguide-integrated EO modulators utilize sputtered Al_(0.904)Sc_(0.096)N thin films as the light-guiding medium,with the entire fabrication process being compatible with complementary metaloxide-semiconductor(CMOS)technology.We extract the in-device effective EO coefficient of 2.86 pm/V at12 GHz.The devices show a minimum half-wave voltage-length product of 3.12 V·cm at a modulation frequency of 14 GHz,and achieve a 3-dB modulation bandwidth of approximately 22 GHz.Our work provides a promising modulation scheme for cost-effective silicon-integrated photonics systems.
基金Research reported in this publication was supported in part by the NSF and SC EPSCoR/IDeA Program under NSF Award#OIA-1655740(GEAR CRP 20-GC02,23-GC01)and NSF Award No.2030128,2110033supported in part by the US Department of Energy,Office of Science,Office of Workforce Development for Teachers and Scientists(WDTS)under the Visiting Faculty Program(VFP)+1 种基金support from the Air Force Office of Scientific Research under Award No.FA9550-22-1-0349 and National Science Foundation under Award No.DMR-2326944 and No.DMR-2340773the support from the program of Educational Department of Liaoning Province(grant no.LQGD2020008).
文摘Optical control of magnons in two-dimensional(2D)materials promises new functionalities for spintronics and magnonics in atomically thin devices.Here,we report control of magnon dynamics,using laser polarization,in a ferromagnetic van der Waals(vdW)material,Fe3.6Co1.4GeTe2.The magnon amplitude,frequency,and lifetime are controlled and monitored by time-resolved pump-probe spectroscopy.We show substantial(over 25%)and continuous modulation of magnon dynamics as a function of incident laser polarization.Our results suggest that the modification of the effective demagnetization field and magnetic anisotropy by the pump laser pulses with different polarizations is due to anisotropic optical absorption.This implies that pump laser pulses modify the local spin environment,which enables the launch of magnons with tunable dynamics.Our first-principles calculations confirm the anisotropic optical absorption of different crystal orientations.Our findings suggest a new route for the development of opto-spintronic or opto-magnonic devices.
