AFM local oxidation nanopatterning of a high mobility shallow 2D hole gas

L. P. Rokhinson; D. C. Tsui; L. N. Pfeiffer; K. W. West

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AFM local oxidation nanopatterning of a high mobility shallow 2D hole gas

L. P. Rokhinson·D. C. Tsui·L. N. Pfeiffer·K. W. West

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Abstract

Recently developed AFM local anodic oxidation (LAO) technique offers a convenient way of patterning nanodevices, but imposes even more stringent requirements on the underlying quantum well structure. We developed a new very shallow quantum well design which allows the depth and density of the 2D gas to be independently controlled during the growth. A high mobility (0.5 10^6 cm^2/Vs at 4.2 K) 2D hole gas just 350A below the surface is demonstrated. A quantum point contact, fabricated by AFM LAO nanopatterning from this wafer, shows 9 quantum steps at 50 mK.

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L. P. Rokhinson, D. C. Tsui, L. N. Pfeiffer, K. W. West. 2003-03-02. AFM local oxidation nanopatterning of a high mobility shallow 2D hole gas. https://arxiv.org/abs/cond-mat/0303011

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