Lee, Kyoung Jin

The orbital Hall effect describes the generation of the orbital current flowing in a perpendicular direction to an external electric field, analogous to the spin Hall effect. As the orbital current carries the angular momentum as the spin current does, injection of the orbital current into a ferromagnet can result in torque on the magnetization, which provides a way to detect the orbital Hall effect. With this motivation, we examine the current-induced spin-orbit torques in various ferromagnet/h

We studied current-induced magnetic switching and excitations in structures comprising a free layer with in-plane magnetization traversed by a current with perpendicular-to-plane spin polarization. We derived analytical solutions from the Landau–Lifshitz–Gilbert equation including the spin-torque term, and compared them to numerical simulations within the single domain assumption. Taking into account the criterion of thermal stability, the magnetization switching in nanostructures of typical siz

Solid electrolyte memories utilizing voltage-induced resistance change display the capability of multilevel switching, but understanding of the microscopic switching mechanism has been left incomplete. Here, in situ TEM observation of voltage-induced changes in the microstructure of a solid electrolyte memory is reported, revealing that the multilevel switching originates from the growth of multiple conducting filaments with nanometer-sized diameter and spacing. Detailed facts of importance to s

Exploiting spin transport increases the functionality of electronic devices and enables such devices to overcome physical limitations related to speed and power. Utilizing the Rashba effect at the interface of heterostructures provides promising opportunities toward the development of high-performance devices because it enables electrical control of the spin information. Herein, the focus is mainly on progress related to the two most compelling devices that exploit the Rashba effect: spin transi

BACKGROUND: Two-dimensional (2D) speckle imaging has shown that it could evaluate not only regional but also global strain (epsilon) and strain rate (SR) of the left and right ventricles. There are no data for global epsilon/SR imaging for left atrial (LA) function evaluation. METHODS: A total of 54 subjects (37 men; mean age, 44 +/- 10 years) with normal treadmill exercise stress echocardiography and no coronary risk factors were enrolled. Global longitudinal LA epsilon/SR data obtained by 2D s