Quantum spin dynamics

Abstract:

Low temperature photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopy of high purity ErSc(2)N@C(80) and Er(2)ScN@C(80) fullerenes reveal at least two metastable configurations of the Er(3+) ion within the cage, consistent with previous observations from x-ray diffraction. Using PLE measurements at a number of different emission wavelengths we have characterized the ground state, (4)I(152), and the first excited state, (4)I(132), of the various Er(3+) configurations and their crystal-field splitting. We present detailed energy level diagrams for the ground and excited states of the two dominant configurations of ErSc(2)N@C(80) and Er(2)ScN@C(80).

Abstract:

We review recent progress towards implementing quantum information processing protocols using electron and nuclear magnetic resonance in the molecule 14N@C60. Using conventional spectrometers, we measure the errors inherent in quantum manipulations of spins. By applying composite pulses, we correct the dominant error to a high degree. Identifying a two qubit computational basis out of the electron and nuclear spin levels of 14N@C60, we implement an ultrafast phase gate on the nuclear qubit by exciting an electron spin transition. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.

Abstract:

Fullerenes have attracted interest as materials for next-generation electronic devices. Considerable effort has been focused on the chemical functionalization of fullerenes. Fullerene dimers possess interesting photophysical effects. Herein we present an overview of our efforts on the synthesis and characterization of different types of fullerene dimers such as directly bonded dimers, a short chain C60 dimer and other dimers with bridge molecules of varying length. By choosing the bridge-molecule one can control the interfullerene spacing and thus tune the electronic interaction between the fullerenes. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.