Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: On the direct insulator-quantum Hall transition in two-dimensional electron systems in the vicinity of nanoscaled scatterers | Liang et al. Nanoscale Research Letters 2011 6 131 http content 6 1 131 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access On the direct insulator-quantum Hall transition in two-dimensional electron systems in the vicinity of nanoscaled scatterers 1 2 1 1 1 3 4 Chi-Te Liang Li-Hung Lin Kuang Yao Chen Shun-Tsung Lo Yi-Ting Wang Dong-Sheng Lou Gil-Ho Kim Yuan-Huei Chang1 Yuichi Ochiai5 Nobuyuki Aoki5 Jeng-Chung Chen3 Yiping Lin3 Chun-Feng Huang6 Sheng-Di Lin7 David A Ritchie8 Abstract A direct insulator-quantum Hall I-QH transition corresponds to a crossover transition from the insulating regime to a high Landau level filling factor V 2 QH state. Such a transition has been attracting a great deal of both experimental and theoretical interests. In this study we present three different two-dimensional electron systems 2DESs which are in the vicinity of nanoscaled scatterers. All these three devices exhibit a direct I-QH transition and the transport properties under different nanaoscaled scatterers are discussed. Introduction The simultaneous presence of disorder and a strong enough magnetic field B can lead to a wide variety of interesting physical phenomena. For example the integer quantum Hall effect is one of the most exciting effects in two-dimensional electron systems 2DES in which the electrons are usually confined in layers of the nanoscale 1 . In an integer quantum Hall QH state the current is carried by the one-dimensional edge channels because of the localization effects. It has been shown that with sufficient amount of disorder a 2DES can undergo a B-induced insulator to quantum Hall transition 2-5 . Experimental evidence for such an insulator-quantum Hall I-QH transition is an approximately temperature T -independent point in the measured longitudinal resistivity of a 2DES 3-5 . The I-QH transition continues to attract a great deal of interest both experimentally and theoretically as it may shed light on .
