通过外延岩盐结构MgZnO薄膜的带隙调控来控制自旋相关隧穿

Controlling spin-dependent tunneling by bandgap tuning in epitaxial rocksalt MgZnO films.

作者信息

Li D L, Ma Q L, Wang S G, Ward R C C, Hesjedal T, Zhang X-G, Kohn A, Amsellem E, Yang G, Liu J L, Jiang J, Wei H X, Han X F

机构信息

State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.

Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, UK.

出版信息

Sci Rep. 2014 Dec 2;4:7277. doi: 10.1038/srep07277.

DOI:10.1038/srep07277

PMID:25451163

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC4250913/

Abstract

Widespread application of magnetic tunnel junctions (MTJs) for information storage has so far been limited by the complicated interplay between tunnel magnetoresistance (TMR) ratio and the product of resistance and junction area (RA). An intricate connection exists between TMR ratio, RA value and the bandgap and crystal structure of the barrier, a connection that must be unravelled to optimise device performance and enable further applications to be developed. Here, we demonstrate a novel method to tailor the bandgap of an ultrathin, epitaxial Zn-doped MgO tunnel barrier with rocksalt structure. This structure is attractive due to its good Δ1 spin filtering effect, and we show that MTJs based on tunable MgZnO barriers allow effective balancing of TMR ratio and RA value. In this way spin-dependent transport properties can be controlled, a key challenge for the development of spintronic devices.

摘要

迄今为止，磁隧道结（MTJs）在信息存储方面的广泛应用受到隧道磁电阻（TMR）比率与电阻和结面积乘积（RA）之间复杂相互作用的限制。TMR比率、RA值与势垒的带隙和晶体结构之间存在着错综复杂的联系，必须解开这种联系才能优化器件性能并开发更多应用。在此，我们展示了一种新颖的方法，可定制具有岩盐结构的超薄外延Zn掺杂MgO隧道势垒的带隙。这种结构因其良好的Δ1自旋过滤效应而颇具吸引力，并且我们表明基于可调谐MgZnO势垒的MTJs能够有效平衡TMR比率和RA值。通过这种方式，可以控制自旋相关的输运特性，这是自旋电子器件发展的一个关键挑战。