Quantum Transport Research Lab
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  Many-Particle Physics in Ultracold 2D Electron Systems (Knuuttila)  
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Experiments in 2D electron system (2DES) can be turned by many “knobs”, and multitude many-particle electronic phases and phase transitions can be studied: fractional charged quantum fluid, Wigner lattices, Luttinger liquid, Stripes and liquid crystal-like phases, and Skyrmions, to name a few. Not unlike in AMO where Bose-Einstein condensation was discovered in ultracold atoms, the frontier of 2DES physics is on ultracold electrons. In collaboration with Columbia (Prof. Horst Stormer), Princeton (Prof. Dan Tsui), Stanford (Prof. Doug Osheroff), and funded by DOE, we have been pursuing a major research project (submillikelvin demagnetization refrigerator for solid state research) for experiments on ultracold electrons in low-D semiconductors and nanostructures. One of the objectives is to searching for exotic many-particle electronic states that obey non-Abelien statistics, but there are much more: cooling electrons to lower than few millikelvin becomes increasingly relevant to general issues of quantum decoherence and phase transitions in electronic systems including mesoscopic metals, quantum dots, and quantum magnets. With the capability to cool 2D electrons to lower temperature, we will develop two important tools for studying many-particle states: tunneling into edge of the quantum fluid and NMR for nuclear spins in the host materials (which in turn reflect the spin states in the 2DES).

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    Novel DC Transport Phenomena and Effect in a AC Driven Quantum Well (Yang, Stone, Yuan)  




Electrical transport of a 2DES exposed to a high frequency (from GHz to THz) driving electromagnetic wave is directly relevant to emerging issues concerning spintronics and quantum information processing. Fundamentally new phenomena of magnetoresistance oscillation and zero-resistance/zero-conductance have been discovered in our lab during the recent years (Phys. Today, Search & Discovery April 2003). We will continue to explore this new effect and its physics.

    SHPM Imaging of Current Distribution in 2DES (Yuan)

One ongoing project is to develop a scanning Hall probe microscopy for simultaneously imaging the electrical current pattern formation and measuring dc transport. If this is successful we will be able to study the domain states proposed by theories in the radiation induced zero-resistance states.

    Si-Based Nanoelectronics (Yang)      

Dr. Rui-Rui Du
Rice University Physics & Astronomy
Dell Butcher Hall Rm. 170
1900 Rice Blvd. Ent. 20
Houston, TX 77005

>Office Phone: 1-713-348-5780

>Lab Phone/Fax: 1-713-348-5719


Supported by a DARPA grant (University of Illinois) “Wavefunction engineering of individual donors for Si-based quantum computers” we have been participating in a quantum information project. The goal of this project is to place individual phosphorous (P) donors into silicon with atomic precision, and to demonstrate electrical control over the coupling between them as a function of their spin states. Our group is responsible for quantum transport measurement of the Si-nanostructures produced by this atom-scale STM patterning technique. We have shown that an ultradense (about 3 orders of magnitude higher than usual 2DES in GaAs) P donor sheets can be formed using this technique, and transport shows a metallic conduction at low temperatures. Recently a nano-sized Aharanov-Bohm ring has been fabricated and verified by our magnetotrasport.

  Fractional Quantum Hall Effect Experiments at NHMFL (Zhang, Knuuttila)      
    Magnetotransport in Two Dimensional Electron/Hole System (Dai)
Rice Physics & Astronomy
Page Last Updated 1-06-09 by Kristjan Stone