Princeton University

This is a multidisciplinary effort to obtain the best platform for topological quantum computing.  Such a quantum computer would be millions of times more powerful than the best current supercomputer because, using quantum mechanical phenomena, one could manipulate a vast amount of information with a relatively small number of qubits.  One way of defeating the biggest obstacle, decoherence of qubits, is through the use of topology: the information is encoded in a non-local way so that local defects do not affect the qubits.  Recently, it has been theoretically realized that among the best candidates for such topologically ordered phases are certain exotic states of electrons confined to two dimensions in a magnetic field, called fractional quantum Hall states.  The qubits are the quasi-particle excitations of these states, and their robustness to local decoherence is due to the fact that they might obey the so-called non Abelian statistics which describe how the system changes when exchanging indistinguishable excitations.  These states, however, are extremely fragile and their statistics are not known.  The solution to obtaining a viable topological quantum computing platform lies in a concerted effort that combines powerful experimental and engineering techniques with advanced theoretical physics and numerical simulations that will push the boundaries of today’s computing techniques.