Quantum Information Processing: Spingineering the Future

SPEAKER: Andrew J. Landahl, Research Assistant Professor, Information Physics Group, University of New MexicoABSTRACT: The spin of a quantum particle is a natural candidate for storing quantum information. A number of technologies are based on this idea, including quantum dots, optical lattices, and nuclear magnetic resonance. Devising new protocols for acquiring, processing, and transmitting information in these systems is a "spingineering" task that current and future generations of information technology researchers will face.I will present my work on three specific "spingineering" research problems, one each from the areas of communication, computation, and error correction. First I will show how to engineer a spin network to serve as a "quantum communication bus" that, in the absence of noise, allows arbitrary-distance perfect-fidelity quantum communication. Then I will show how to engineer a spin chain to serve as a "programmable universal quantum computer" that can execute an arbitrary program on an arbitrary input, where both the program and the data are encoded in the initial state of the spins. Finally, I will show how to perform "continuous-time quantum error correction" on a spin network by optimizing a feedback loop that uses weak measurements and Hamiltonian controls.These problems demonstrate that "spingineering" requires a broad-based theoretical background to achieve an engineering solution; in this talk the solutions will rely on quantum mechanics, algebraic coding theory, random walk theory, and feedback control theory.BIO: Andrew Landahl is a Research Assistant Professor in the Information Physics Group at the University of New Mexico. He was a Hewlett-Packard/MIT Postdoctoral Fellow from 2002-05 under the supervision of Professor Seth Lloyd. He earned Physics M.S. and Ph.D. degrees at Caltech (2000 and 2002) under the supervision of Professor John Preskill and earned Physics and Mathematics B.S. degrees, Summa cum Laude, at Virginia Tech (1996), with an Honors Thesis supervised by Professor Lay-Nam Chang.Professor Landahl's research spans the areas of quantum computing, quantum information, and quantum control. His research accomplishments include the fastest quantum algorithm for searching an ordered list, a spin-chain bus enabling lossless quantum communication, a topologically-protected fault-tolerant quantum memory, a printed quantum circuit architecture, and the theory of continuous-time quantum error correction. His refereed publications average over 40 citations per paper. He has supervised or co-supervised the research of seven students.Professor Landahl is a member of the American Physical Society (APS), Institute of Electrical and Electronics Engineers (IEEE), and the Association for Computing Machinery (ACM). He served as a Grand Awards Judge for the 2007 Intel International Science and Engineering Fair (ISEF) and mentored a Siemens-Westinghouse Regional Finalist in 2003-04. He currently serves as Chair of the Local Organizing Committee for QIP 2009, a high-profile annual international conference of over 350 researchers in the field of quantum information to be held in Santa Fe, NM in January 2009.HOST: Prof. Todd Brun, tbrun@usc.edu

Location: Frank R. Seaver Science Center (SSC) - 319

Audiences: Everyone Is Invited

Contact: Mayumi Thrasher