Search

Current pulse driven Néel vector rotation in metallic antiferromagnets is one of the most promising concepts in antiferromagnetic spintronics. We show microscopically that the Néel vector of epitaxial thin films of the prototypical compound Mn2Au can be reoriented reversibly in the complete area of cross shaped device structures using single current pulses. The resulting domain pattern with aligned staggered magnetization is long term stable enabling memory applications. We achieve this switching with low heating of ≈20 K, which is promising regarding fast and efficient devices without the need for thermal activation. Current polarity dependent reversible domain wall motion demonstrates a Néel spin-orbit torque acting on the domain walls. Antiferromagnets have an inbuilt resilience to external magnetic fields and intrinsically fast dynamics, properties that have garnered interest in the hope that they could be used for antiferromagnet memories. Central to this are Neel spin-orbit torques, which can switch the individual sublattices of the antiferromagnet. Here, Reimers et al demonstrate complete and reversible current induced switching of the Neel vector in Mn2Au. [ABSTRACT FROM AUTHOR]

In antiferromagnetic spintronics, the read-out of the staggered magnetization or Néel vector is the key obstacle to harnessing the ultra-fast dynamics and stability of antiferromagnets for novel devices. Here, we demonstrate strong exchange coupling of Mn2Au, a unique metallic antiferromagnet that exhibits Néel spin-orbit torques, with thin ferromagnetic Permalloy layers. This allows us to benefit from the well-established read-out methods of ferromagnets, while the essential advantages of antiferromagnetic spintronics are only slightly diminished. We show one-to-one imprinting of the antiferromagnetic on the ferromagnetic domain pattern. Conversely, alignment of the Permalloy magnetization reorients the Mn2Au Néel vector, an effect, which can be restricted to large magnetic fields by tuning the ferromagnetic layer thickness. To understand the origin of the strong coupling, we carry out high resolution electron microscopy imaging and we find that our growth yields an interface with a well-defined morphology that leads to the strong exchange coupling. Antiferromagnets offer faster operation speed and immunity to stray fields, however, readout of the Neel vector is difficult. Here, Bommanaboyena et al present a heterostructure of a ferromagnet and antiferromagnet, combining easy readout with the benefits of antiferromagnetic spintronics. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinicopathological features and differential diagnosis of metastatic tumors in the lung. Methods: The clinicopathological data of 226 metastatic tumors in the lung were collected at Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, from January 2014 to December 2018, and the pathomorphological characteristics were analyzed. Results: There were 84 males and 142 females, with an age range from 13 to 77 years. There were 122 patients with multiple pulmonary nodules and 104 patients with solitary pulmonary nodule. The tumors of the highest frequencies were colorectal cancer ( n =59), followed by trophoblast tumor ( n =44), kidney cancer ( n =31), breast cancer ( n =20), cervix cancer ( n =14), and urinary urothelium cancer ( n =8). The time from the diagnosis of primary tumors to metastasis and the status of surgical treatment varied by tumor origin. The morphology of metastatic lung tumors overlapped with that of the primary tumors to some extent. The relative specific morphological characteristics and the presence of carcinoma in situ surrounding the tumors should be carefully searched for to confirm the tumor origin. The metastatic tumors of the lung had morphological characteristics, immunohistochemical TTF1 (-) and tumor of various sources, while the primary tumor differentiation had relatively specific antibodies: colorectal cancer CK20 (+), CDX2 (+), CK7 (-); malignant trophoblastic tumor, HCG (+); renal clear cell carcinoma CD10 (+), vimentin (+), CK7 (-); breast cancer, GATA3 and ER (+); cervical cancer, p16 (+); urothelial carcinoma, CK20, p63 and GATA3 (+). Conclusions: There is overlap between pulmonary metastatic tumor and primary tumor in morphology. Therefore, the diagnosis should be made by combining clinical history, pathological morphology and immunophenotypic characteristics.