电阻式核磁共振测量的最新进展

Resistively detected nuclear magnetic resonance: recent developments

电阻式核磁共振(RDNMR)测量是1988年由德国马普所的von Klitzing研究小组针对GaAs二维电子气中少量核自旋的探测而提出的一种具有超高灵敏度的实验技术.目前,RDNMR已经成为研究单层或双层GaAs二维电子气核自旋和电子自旋特性的重要手段.由于为实现电阻式核磁共振测量所建立的动态核极化方法强烈依赖于GaAs特有的材料属性,至今这一技术一直没有扩展应用到其他半导体低维系统中.最近,本研究小组发展了一种动态核极化新方法,成功实现了对典型窄带半导体锑化铟(InSb)二维电子气的电阻式核磁共振测量.本文在介绍电阻式核磁共振测量工作原理及已建立的典型动态核极化方法的基础上,着重讨论所提出的动态核极化新方法的机理、实验结果以及对今后研究的展望.

The resistively detected nuclear magnetic resonance（RDNMR）,a high-sensitivity NMR technique developed by Klaus von Klitzing＇s group in 1988,is used to investigate exotic electron and nuclear spin properties in GaAs two-dimensional electron gases（2DEGs）. Because the dynamic nuclear polarization（DNP） approach required for the RDNMR demonstration is strongly dependent on unique material properties of GaAs,this highly-sensitive technique has not yet been applied to 2DEGs confined in other host semiconductors. More recently,we have developed a novel DNP method for demonstration of RDNMR in a 2DEG within the typical narrow-gap semiconductor InSb.In this article,we focus on the discussion of our newly-developed DNP method,experimental details and results as well as future prospects after some preliminary remarks on the principles of RDNMR and DNP.